VOL-1558 Update vendored voltha-go and other items

Result of running dep ensure.  golang openolt now
builds.

Also update dockerfile to used specific alpine version

Change-Id: I1e5407e25bb0636a241a0650d1e44e5df567f44b
diff --git a/vendor/github.com/opencord/voltha-go/db/model/revision.go b/vendor/github.com/opencord/voltha-go/db/model/revision.go
new file mode 100644
index 0000000..2c10137
--- /dev/null
+++ b/vendor/github.com/opencord/voltha-go/db/model/revision.go
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+
+ * 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 model
+
+type Revision interface {
+	Finalize(bool)
+	SetConfig(revision *DataRevision)
+	GetConfig() *DataRevision
+	Drop(txid string, includeConfig bool)
+	StorageDrop(txid string, includeConfig bool)
+	SetChildren(name string, children []Revision)
+	GetChildren(name string) []Revision
+	SetAllChildren(children map[string][]Revision)
+	GetAllChildren() map[string][]Revision
+	SetHash(hash string)
+	GetHash() string
+	ClearHash()
+	SetupWatch(key string)
+	SetName(name string)
+	GetName() string
+	SetBranch(branch *Branch)
+	GetBranch() *Branch
+	Get(int) interface{}
+	GetData() interface{}
+	GetNode() *node
+	LoadFromPersistence(path string, txid string) []Revision
+	UpdateData(data interface{}, branch *Branch) Revision
+	UpdateChildren(name string, children []Revision, branch *Branch) Revision
+	UpdateAllChildren(children map[string][]Revision, branch *Branch) Revision
+}