rebase: vendor dependencies for Vault API

Uses github.com/libopenstorage/secrets to communicate with Vault. This
removes the need for maintaining our own limited Vault APIs.

By adding the new dependency, several other packages got updated in the
process. Unused indirect dependencies have been removed from go.mod.

Signed-off-by: Niels de Vos <ndevos@redhat.com>

vendor/google.golang.org/protobuf/runtime/protoimpl/impl.go

@@ -0,0 +1,44 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package protoimpl contains the default implementation for messages
+// generated by protoc-gen-go.
+//
+// WARNING: This package should only ever be imported by generated messages.
+// The compatibility agreement covers nothing except for functionality needed
+// to keep existing generated messages operational. Breakages that occur due
+// to unauthorized usages of this package are not the author's responsibility.
+package protoimpl
+
+import (
+	"google.golang.org/protobuf/internal/filedesc"
+	"google.golang.org/protobuf/internal/filetype"
+	"google.golang.org/protobuf/internal/impl"
+)
+
+// UnsafeEnabled specifies whether package unsafe can be used.
+const UnsafeEnabled = impl.UnsafeEnabled
+
+type (
+	// Types used by generated code in init functions.
+	DescBuilder = filedesc.Builder
+	TypeBuilder = filetype.Builder
+
+	// Types used by generated code to implement EnumType, MessageType, and ExtensionType.
+	EnumInfo      = impl.EnumInfo
+	MessageInfo   = impl.MessageInfo
+	ExtensionInfo = impl.ExtensionInfo
+
+	// Types embedded in generated messages.
+	MessageState     = impl.MessageState
+	SizeCache        = impl.SizeCache
+	WeakFields       = impl.WeakFields
+	UnknownFields    = impl.UnknownFields
+	ExtensionFields  = impl.ExtensionFields
+	ExtensionFieldV1 = impl.ExtensionField
+
+	Pointer = impl.Pointer
+)
+
+var X impl.Export