diff --git a/vendor/go.etcd.io/etcd/clientv3/client.go b/vendor/go.etcd.io/etcd/clientv3/client.go
new file mode 100644
index 0000000..445ecfe
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/clientv3/client.go
@@ -0,0 +1,668 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package clientv3
+
+import (
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/google/uuid"
+	"go.etcd.io/etcd/clientv3/balancer"
+	"go.etcd.io/etcd/clientv3/balancer/picker"
+	"go.etcd.io/etcd/clientv3/balancer/resolver/endpoint"
+	"go.etcd.io/etcd/etcdserver/api/v3rpc/rpctypes"
+	"go.etcd.io/etcd/pkg/logutil"
+	"go.uber.org/zap"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/keepalive"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
+)
+
+var (
+	ErrNoAvailableEndpoints = errors.New("etcdclient: no available endpoints")
+	ErrOldCluster           = errors.New("etcdclient: old cluster version")
+
+	roundRobinBalancerName = fmt.Sprintf("etcd-%s", picker.RoundrobinBalanced.String())
+)
+
+func init() {
+	lg := zap.NewNop()
+	if os.Getenv("ETCD_CLIENT_DEBUG") != "" {
+		var err error
+		lg, err = zap.NewProductionConfig().Build() // info level logging
+		if err != nil {
+			panic(err)
+		}
+	}
+	balancer.RegisterBuilder(balancer.Config{
+		Policy: picker.RoundrobinBalanced,
+		Name:   roundRobinBalancerName,
+		Logger: lg,
+	})
+}
+
+// Client provides and manages an etcd v3 client session.
+type Client struct {
+	Cluster
+	KV
+	Lease
+	Watcher
+	Auth
+	Maintenance
+
+	conn *grpc.ClientConn
+
+	cfg           Config
+	creds         *credentials.TransportCredentials
+	balancer      balancer.Balancer
+	resolverGroup *endpoint.ResolverGroup
+	mu            *sync.Mutex
+
+	ctx    context.Context
+	cancel context.CancelFunc
+
+	// Username is a user name for authentication.
+	Username string
+	// Password is a password for authentication.
+	Password string
+	// tokenCred is an instance of WithPerRPCCredentials()'s argument
+	tokenCred *authTokenCredential
+
+	callOpts []grpc.CallOption
+
+	lg *zap.Logger
+}
+
+// New creates a new etcdv3 client from a given configuration.
+func New(cfg Config) (*Client, error) {
+	if len(cfg.Endpoints) == 0 {
+		return nil, ErrNoAvailableEndpoints
+	}
+
+	return newClient(&cfg)
+}
+
+// NewCtxClient creates a client with a context but no underlying grpc
+// connection. This is useful for embedded cases that override the
+// service interface implementations and do not need connection management.
+func NewCtxClient(ctx context.Context) *Client {
+	cctx, cancel := context.WithCancel(ctx)
+	return &Client{ctx: cctx, cancel: cancel}
+}
+
+// NewFromURL creates a new etcdv3 client from a URL.
+func NewFromURL(url string) (*Client, error) {
+	return New(Config{Endpoints: []string{url}})
+}
+
+// NewFromURLs creates a new etcdv3 client from URLs.
+func NewFromURLs(urls []string) (*Client, error) {
+	return New(Config{Endpoints: urls})
+}
+
+// Close shuts down the client's etcd connections.
+func (c *Client) Close() error {
+	c.cancel()
+	c.Watcher.Close()
+	c.Lease.Close()
+	if c.resolverGroup != nil {
+		c.resolverGroup.Close()
+	}
+	if c.conn != nil {
+		return toErr(c.ctx, c.conn.Close())
+	}
+	return c.ctx.Err()
+}
+
+// Ctx is a context for "out of band" messages (e.g., for sending
+// "clean up" message when another context is canceled). It is
+// canceled on client Close().
+func (c *Client) Ctx() context.Context { return c.ctx }
+
+// Endpoints lists the registered endpoints for the client.
+func (c *Client) Endpoints() (eps []string) {
+	// copy the slice; protect original endpoints from being changed
+	eps = make([]string, len(c.cfg.Endpoints))
+	copy(eps, c.cfg.Endpoints)
+	return
+}
+
+// SetEndpoints updates client's endpoints.
+func (c *Client) SetEndpoints(eps ...string) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.cfg.Endpoints = eps
+	c.resolverGroup.SetEndpoints(eps)
+}
+
+// Sync synchronizes client's endpoints with the known endpoints from the etcd membership.
+func (c *Client) Sync(ctx context.Context) error {
+	mresp, err := c.MemberList(ctx)
+	if err != nil {
+		return err
+	}
+	var eps []string
+	for _, m := range mresp.Members {
+		eps = append(eps, m.ClientURLs...)
+	}
+	c.SetEndpoints(eps...)
+	return nil
+}
+
+func (c *Client) autoSync() {
+	if c.cfg.AutoSyncInterval == time.Duration(0) {
+		return
+	}
+
+	for {
+		select {
+		case <-c.ctx.Done():
+			return
+		case <-time.After(c.cfg.AutoSyncInterval):
+			ctx, cancel := context.WithTimeout(c.ctx, 5*time.Second)
+			err := c.Sync(ctx)
+			cancel()
+			if err != nil && err != c.ctx.Err() {
+				lg.Lvl(4).Infof("Auto sync endpoints failed: %v", err)
+			}
+		}
+	}
+}
+
+type authTokenCredential struct {
+	token   string
+	tokenMu *sync.RWMutex
+}
+
+func (cred authTokenCredential) RequireTransportSecurity() bool {
+	return false
+}
+
+func (cred authTokenCredential) GetRequestMetadata(ctx context.Context, s ...string) (map[string]string, error) {
+	cred.tokenMu.RLock()
+	defer cred.tokenMu.RUnlock()
+	return map[string]string{
+		rpctypes.TokenFieldNameGRPC: cred.token,
+	}, nil
+}
+
+func (c *Client) processCreds(scheme string) (creds *credentials.TransportCredentials) {
+	creds = c.creds
+	switch scheme {
+	case "unix":
+	case "http":
+		creds = nil
+	case "https", "unixs":
+		if creds != nil {
+			break
+		}
+		tlsconfig := &tls.Config{}
+		emptyCreds := credentials.NewTLS(tlsconfig)
+		creds = &emptyCreds
+	default:
+		creds = nil
+	}
+	return creds
+}
+
+// dialSetupOpts gives the dial opts prior to any authentication.
+func (c *Client) dialSetupOpts(creds *credentials.TransportCredentials, dopts ...grpc.DialOption) (opts []grpc.DialOption, err error) {
+	if c.cfg.DialKeepAliveTime > 0 {
+		params := keepalive.ClientParameters{
+			Time:                c.cfg.DialKeepAliveTime,
+			Timeout:             c.cfg.DialKeepAliveTimeout,
+			PermitWithoutStream: c.cfg.PermitWithoutStream,
+		}
+		opts = append(opts, grpc.WithKeepaliveParams(params))
+	}
+	opts = append(opts, dopts...)
+
+	// Provide a net dialer that supports cancelation and timeout.
+	f := func(dialEp string, t time.Duration) (net.Conn, error) {
+		proto, host, _ := endpoint.ParseEndpoint(dialEp)
+		select {
+		case <-c.ctx.Done():
+			return nil, c.ctx.Err()
+		default:
+		}
+		dialer := &net.Dialer{Timeout: t}
+		return dialer.DialContext(c.ctx, proto, host)
+	}
+	opts = append(opts, grpc.WithDialer(f))
+
+	if creds != nil {
+		opts = append(opts, grpc.WithTransportCredentials(*creds))
+	} else {
+		opts = append(opts, grpc.WithInsecure())
+	}
+
+	// Interceptor retry and backoff.
+	// TODO: Replace all of clientv3/retry.go with interceptor based retry, or with
+	// https://github.com/grpc/proposal/blob/master/A6-client-retries.md#retry-policy
+	// once it is available.
+	rrBackoff := withBackoff(c.roundRobinQuorumBackoff(defaultBackoffWaitBetween, defaultBackoffJitterFraction))
+	opts = append(opts,
+		// Disable stream retry by default since go-grpc-middleware/retry does not support client streams.
+		// Streams that are safe to retry are enabled individually.
+		grpc.WithStreamInterceptor(c.streamClientInterceptor(c.lg, withMax(0), rrBackoff)),
+		grpc.WithUnaryInterceptor(c.unaryClientInterceptor(c.lg, withMax(defaultUnaryMaxRetries), rrBackoff)),
+	)
+
+	return opts, nil
+}
+
+// Dial connects to a single endpoint using the client's config.
+func (c *Client) Dial(ep string) (*grpc.ClientConn, error) {
+	creds := c.directDialCreds(ep)
+	// Use the grpc passthrough resolver to directly dial a single endpoint.
+	// This resolver passes through the 'unix' and 'unixs' endpoints schemes used
+	// by etcd without modification, allowing us to directly dial endpoints and
+	// using the same dial functions that we use for load balancer dialing.
+	return c.dial(fmt.Sprintf("passthrough:///%s", ep), creds)
+}
+
+func (c *Client) getToken(ctx context.Context) error {
+	var err error // return last error in a case of fail
+	var auth *authenticator
+
+	for i := 0; i < len(c.cfg.Endpoints); i++ {
+		ep := c.cfg.Endpoints[i]
+		// use dial options without dopts to avoid reusing the client balancer
+		var dOpts []grpc.DialOption
+		_, host, _ := endpoint.ParseEndpoint(ep)
+		target := c.resolverGroup.Target(host)
+		creds := c.dialWithBalancerCreds(ep)
+		dOpts, err = c.dialSetupOpts(creds, c.cfg.DialOptions...)
+		if err != nil {
+			err = fmt.Errorf("failed to configure auth dialer: %v", err)
+			continue
+		}
+		dOpts = append(dOpts, grpc.WithBalancerName(roundRobinBalancerName))
+		auth, err = newAuthenticator(ctx, target, dOpts, c)
+		if err != nil {
+			continue
+		}
+		defer auth.close()
+
+		var resp *AuthenticateResponse
+		resp, err = auth.authenticate(ctx, c.Username, c.Password)
+		if err != nil {
+			// return err without retrying other endpoints
+			if err == rpctypes.ErrAuthNotEnabled {
+				return err
+			}
+			continue
+		}
+
+		c.tokenCred.tokenMu.Lock()
+		c.tokenCred.token = resp.Token
+		c.tokenCred.tokenMu.Unlock()
+
+		return nil
+	}
+
+	return err
+}
+
+// dialWithBalancer dials the client's current load balanced resolver group.  The scheme of the host
+// of the provided endpoint determines the scheme used for all endpoints of the client connection.
+func (c *Client) dialWithBalancer(ep string, dopts ...grpc.DialOption) (*grpc.ClientConn, error) {
+	_, host, _ := endpoint.ParseEndpoint(ep)
+	target := c.resolverGroup.Target(host)
+	creds := c.dialWithBalancerCreds(ep)
+	return c.dial(target, creds, dopts...)
+}
+
+// dial configures and dials any grpc balancer target.
+func (c *Client) dial(target string, creds *credentials.TransportCredentials, dopts ...grpc.DialOption) (*grpc.ClientConn, error) {
+	opts, err := c.dialSetupOpts(creds, dopts...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to configure dialer: %v", err)
+	}
+
+	if c.Username != "" && c.Password != "" {
+		c.tokenCred = &authTokenCredential{
+			tokenMu: &sync.RWMutex{},
+		}
+
+		ctx, cancel := c.ctx, func() {}
+		if c.cfg.DialTimeout > 0 {
+			ctx, cancel = context.WithTimeout(ctx, c.cfg.DialTimeout)
+		}
+
+		err = c.getToken(ctx)
+		if err != nil {
+			if toErr(ctx, err) != rpctypes.ErrAuthNotEnabled {
+				if err == ctx.Err() && ctx.Err() != c.ctx.Err() {
+					err = context.DeadlineExceeded
+				}
+				cancel()
+				return nil, err
+			}
+		} else {
+			opts = append(opts, grpc.WithPerRPCCredentials(c.tokenCred))
+		}
+		cancel()
+	}
+
+	opts = append(opts, c.cfg.DialOptions...)
+
+	dctx := c.ctx
+	if c.cfg.DialTimeout > 0 {
+		var cancel context.CancelFunc
+		dctx, cancel = context.WithTimeout(c.ctx, c.cfg.DialTimeout)
+		defer cancel() // TODO: Is this right for cases where grpc.WithBlock() is not set on the dial options?
+	}
+
+	conn, err := grpc.DialContext(dctx, target, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return conn, nil
+}
+
+func (c *Client) directDialCreds(ep string) *credentials.TransportCredentials {
+	_, hostPort, scheme := endpoint.ParseEndpoint(ep)
+	creds := c.creds
+	if len(scheme) != 0 {
+		creds = c.processCreds(scheme)
+		if creds != nil {
+			c := *creds
+			clone := c.Clone()
+			// Set the server name must to the endpoint hostname without port since grpc
+			// otherwise attempts to check if x509 cert is valid for the full endpoint
+			// including the scheme and port, which fails.
+			host, _ := endpoint.ParseHostPort(hostPort)
+			clone.OverrideServerName(host)
+			creds = &clone
+		}
+	}
+	return creds
+}
+
+func (c *Client) dialWithBalancerCreds(ep string) *credentials.TransportCredentials {
+	_, _, scheme := endpoint.ParseEndpoint(ep)
+	creds := c.creds
+	if len(scheme) != 0 {
+		creds = c.processCreds(scheme)
+	}
+	return creds
+}
+
+// WithRequireLeader requires client requests to only succeed
+// when the cluster has a leader.
+func WithRequireLeader(ctx context.Context) context.Context {
+	md := metadata.Pairs(rpctypes.MetadataRequireLeaderKey, rpctypes.MetadataHasLeader)
+	return metadata.NewOutgoingContext(ctx, md)
+}
+
+func newClient(cfg *Config) (*Client, error) {
+	if cfg == nil {
+		cfg = &Config{}
+	}
+	var creds *credentials.TransportCredentials
+	if cfg.TLS != nil {
+		c := credentials.NewTLS(cfg.TLS)
+		creds = &c
+	}
+
+	// use a temporary skeleton client to bootstrap first connection
+	baseCtx := context.TODO()
+	if cfg.Context != nil {
+		baseCtx = cfg.Context
+	}
+
+	ctx, cancel := context.WithCancel(baseCtx)
+	client := &Client{
+		conn:     nil,
+		cfg:      *cfg,
+		creds:    creds,
+		ctx:      ctx,
+		cancel:   cancel,
+		mu:       new(sync.Mutex),
+		callOpts: defaultCallOpts,
+	}
+
+	lcfg := logutil.DefaultZapLoggerConfig
+	if cfg.LogConfig != nil {
+		lcfg = *cfg.LogConfig
+	}
+	var err error
+	client.lg, err = lcfg.Build()
+	if err != nil {
+		return nil, err
+	}
+
+	if cfg.Username != "" && cfg.Password != "" {
+		client.Username = cfg.Username
+		client.Password = cfg.Password
+	}
+	if cfg.MaxCallSendMsgSize > 0 || cfg.MaxCallRecvMsgSize > 0 {
+		if cfg.MaxCallRecvMsgSize > 0 && cfg.MaxCallSendMsgSize > cfg.MaxCallRecvMsgSize {
+			return nil, fmt.Errorf("gRPC message recv limit (%d bytes) must be greater than send limit (%d bytes)", cfg.MaxCallRecvMsgSize, cfg.MaxCallSendMsgSize)
+		}
+		callOpts := []grpc.CallOption{
+			defaultFailFast,
+			defaultMaxCallSendMsgSize,
+			defaultMaxCallRecvMsgSize,
+		}
+		if cfg.MaxCallSendMsgSize > 0 {
+			callOpts[1] = grpc.MaxCallSendMsgSize(cfg.MaxCallSendMsgSize)
+		}
+		if cfg.MaxCallRecvMsgSize > 0 {
+			callOpts[2] = grpc.MaxCallRecvMsgSize(cfg.MaxCallRecvMsgSize)
+		}
+		client.callOpts = callOpts
+	}
+
+	// Prepare a 'endpoint://<unique-client-id>/' resolver for the client and create a endpoint target to pass
+	// to dial so the client knows to use this resolver.
+	client.resolverGroup, err = endpoint.NewResolverGroup(fmt.Sprintf("client-%s", uuid.New().String()))
+	if err != nil {
+		client.cancel()
+		return nil, err
+	}
+	client.resolverGroup.SetEndpoints(cfg.Endpoints)
+
+	if len(cfg.Endpoints) < 1 {
+		return nil, fmt.Errorf("at least one Endpoint must is required in client config")
+	}
+	dialEndpoint := cfg.Endpoints[0]
+
+	// Use a provided endpoint target so that for https:// without any tls config given, then
+	// grpc will assume the certificate server name is the endpoint host.
+	conn, err := client.dialWithBalancer(dialEndpoint, grpc.WithBalancerName(roundRobinBalancerName))
+	if err != nil {
+		client.cancel()
+		client.resolverGroup.Close()
+		return nil, err
+	}
+	// TODO: With the old grpc balancer interface, we waited until the dial timeout
+	// for the balancer to be ready. Is there an equivalent wait we should do with the new grpc balancer interface?
+	client.conn = conn
+
+	client.Cluster = NewCluster(client)
+	client.KV = NewKV(client)
+	client.Lease = NewLease(client)
+	client.Watcher = NewWatcher(client)
+	client.Auth = NewAuth(client)
+	client.Maintenance = NewMaintenance(client)
+
+	if cfg.RejectOldCluster {
+		if err := client.checkVersion(); err != nil {
+			client.Close()
+			return nil, err
+		}
+	}
+
+	go client.autoSync()
+	return client, nil
+}
+
+// roundRobinQuorumBackoff retries against quorum between each backoff.
+// This is intended for use with a round robin load balancer.
+func (c *Client) roundRobinQuorumBackoff(waitBetween time.Duration, jitterFraction float64) backoffFunc {
+	return func(attempt uint) time.Duration {
+		// after each round robin across quorum, backoff for our wait between duration
+		n := uint(len(c.Endpoints()))
+		quorum := (n/2 + 1)
+		if attempt%quorum == 0 {
+			c.lg.Debug("backoff", zap.Uint("attempt", attempt), zap.Uint("quorum", quorum), zap.Duration("waitBetween", waitBetween), zap.Float64("jitterFraction", jitterFraction))
+			return jitterUp(waitBetween, jitterFraction)
+		}
+		c.lg.Debug("backoff skipped", zap.Uint("attempt", attempt), zap.Uint("quorum", quorum))
+		return 0
+	}
+}
+
+func (c *Client) checkVersion() (err error) {
+	var wg sync.WaitGroup
+	errc := make(chan error, len(c.cfg.Endpoints))
+	ctx, cancel := context.WithCancel(c.ctx)
+	if c.cfg.DialTimeout > 0 {
+		ctx, cancel = context.WithTimeout(ctx, c.cfg.DialTimeout)
+	}
+	wg.Add(len(c.cfg.Endpoints))
+	for _, ep := range c.cfg.Endpoints {
+		// if cluster is current, any endpoint gives a recent version
+		go func(e string) {
+			defer wg.Done()
+			resp, rerr := c.Status(ctx, e)
+			if rerr != nil {
+				errc <- rerr
+				return
+			}
+			vs := strings.Split(resp.Version, ".")
+			maj, min := 0, 0
+			if len(vs) >= 2 {
+				maj, _ = strconv.Atoi(vs[0])
+				min, rerr = strconv.Atoi(vs[1])
+			}
+			if maj < 3 || (maj == 3 && min < 2) {
+				rerr = ErrOldCluster
+			}
+			errc <- rerr
+		}(ep)
+	}
+	// wait for success
+	for i := 0; i < len(c.cfg.Endpoints); i++ {
+		if err = <-errc; err == nil {
+			break
+		}
+	}
+	cancel()
+	wg.Wait()
+	return err
+}
+
+// ActiveConnection returns the current in-use connection
+func (c *Client) ActiveConnection() *grpc.ClientConn { return c.conn }
+
+// isHaltErr returns true if the given error and context indicate no forward
+// progress can be made, even after reconnecting.
+func isHaltErr(ctx context.Context, err error) bool {
+	if ctx != nil && ctx.Err() != nil {
+		return true
+	}
+	if err == nil {
+		return false
+	}
+	ev, _ := status.FromError(err)
+	// Unavailable codes mean the system will be right back.
+	// (e.g., can't connect, lost leader)
+	// Treat Internal codes as if something failed, leaving the
+	// system in an inconsistent state, but retrying could make progress.
+	// (e.g., failed in middle of send, corrupted frame)
+	// TODO: are permanent Internal errors possible from grpc?
+	return ev.Code() != codes.Unavailable && ev.Code() != codes.Internal
+}
+
+// isUnavailableErr returns true if the given error is an unavailable error
+func isUnavailableErr(ctx context.Context, err error) bool {
+	if ctx != nil && ctx.Err() != nil {
+		return false
+	}
+	if err == nil {
+		return false
+	}
+	ev, _ := status.FromError(err)
+	// Unavailable codes mean the system will be right back.
+	// (e.g., can't connect, lost leader)
+	return ev.Code() == codes.Unavailable
+}
+
+func toErr(ctx context.Context, err error) error {
+	if err == nil {
+		return nil
+	}
+	err = rpctypes.Error(err)
+	if _, ok := err.(rpctypes.EtcdError); ok {
+		return err
+	}
+	if ev, ok := status.FromError(err); ok {
+		code := ev.Code()
+		switch code {
+		case codes.DeadlineExceeded:
+			fallthrough
+		case codes.Canceled:
+			if ctx.Err() != nil {
+				err = ctx.Err()
+			}
+		case codes.Unavailable:
+		case codes.FailedPrecondition:
+			err = grpc.ErrClientConnClosing
+		}
+	}
+	return err
+}
+
+func canceledByCaller(stopCtx context.Context, err error) bool {
+	if stopCtx.Err() == nil || err == nil {
+		return false
+	}
+
+	return err == context.Canceled || err == context.DeadlineExceeded
+}
+
+// IsConnCanceled returns true, if error is from a closed gRPC connection.
+// ref. https://github.com/grpc/grpc-go/pull/1854
+func IsConnCanceled(err error) bool {
+	if err == nil {
+		return false
+	}
+	// >= gRPC v1.10.x
+	s, ok := status.FromError(err)
+	if ok {
+		// connection is canceled or server has already closed the connection
+		return s.Code() == codes.Canceled || s.Message() == "transport is closing"
+	}
+	// >= gRPC v1.10.x
+	if err == context.Canceled {
+		return true
+	}
+	// <= gRPC v1.7.x returns 'errors.New("grpc: the client connection is closing")'
+	return strings.Contains(err.Error(), "grpc: the client connection is closing")
+}