VOL-1460 Updated core to use voltha-protos instead of local protos
Moved protos to python directory in order to maintain functionaly of containers built there.
Added capability to do local builds of protos
Added instructions on running dep ensure for getting protos.
Updated github.com/golang/protobuf version to v1.3.1

Change-Id: Ia6ef55f07f0d5dcb5b750d7c37b21b71db85bfc4
diff --git a/vendor/go.etcd.io/etcd/clientv3/balancer/balancer.go b/vendor/go.etcd.io/etcd/clientv3/balancer/balancer.go
index 25dc2b7..3c44e70 100644
--- a/vendor/go.etcd.io/etcd/clientv3/balancer/balancer.go
+++ b/vendor/go.etcd.io/etcd/clientv3/balancer/balancer.go
@@ -36,7 +36,7 @@
 	bb := &builder{cfg}
 	balancer.Register(bb)
 
-	bb.cfg.Logger.Info(
+	bb.cfg.Logger.Debug(
 		"registered balancer",
 		zap.String("policy", bb.cfg.Policy.String()),
 		zap.String("name", bb.cfg.Name),
diff --git a/vendor/go.etcd.io/etcd/clientv3/balancer/grpc1.7-health.go b/vendor/go.etcd.io/etcd/clientv3/balancer/grpc1.7-health.go
index 7d24b93..2153767 100644
--- a/vendor/go.etcd.io/etcd/clientv3/balancer/grpc1.7-health.go
+++ b/vendor/go.etcd.io/etcd/clientv3/balancer/grpc1.7-health.go
@@ -38,10 +38,10 @@
 	unknownService         = "unknown service grpc.health.v1.Health"
 )
 
-// ErrNoAddrAvilable is returned by Get() when the balancer does not have
+// ErrNoAddrAvailable is returned by Get() when the balancer does not have
 // any active connection to endpoints at the time.
 // This error is returned only when opts.BlockingWait is true.
-var ErrNoAddrAvilable = status.Error(codes.Unavailable, "there is no address available")
+var ErrNoAddrAvailable = status.Error(codes.Unavailable, "there is no address available")
 
 type NotifyMsg int
 
@@ -510,7 +510,7 @@
 			return grpc.Address{Addr: ""}, nil, grpc.ErrClientConnClosing
 		}
 		if addr == "" {
-			return grpc.Address{Addr: ""}, nil, ErrNoAddrAvilable
+			return grpc.Address{Addr: ""}, nil, ErrNoAddrAvailable
 		}
 		return grpc.Address{Addr: addr}, func() {}, nil
 	}