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/internal/impl/weak.go

@@ -0,0 +1,74 @@
+// Copyright 2019 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 impl
+
+import (
+	"fmt"
+
+	pref "google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+)
+
+// weakFields adds methods to the exported WeakFields type for internal use.
+//
+// The exported type is an alias to an unnamed type, so methods can't be
+// defined directly on it.
+type weakFields WeakFields
+
+func (w weakFields) get(num pref.FieldNumber) (pref.ProtoMessage, bool) {
+	m, ok := w[int32(num)]
+	return m, ok
+}
+
+func (w *weakFields) set(num pref.FieldNumber, m pref.ProtoMessage) {
+	if *w == nil {
+		*w = make(weakFields)
+	}
+	(*w)[int32(num)] = m
+}
+
+func (w *weakFields) clear(num pref.FieldNumber) {
+	delete(*w, int32(num))
+}
+
+func (Export) HasWeak(w WeakFields, num pref.FieldNumber) bool {
+	_, ok := w[int32(num)]
+	return ok
+}
+
+func (Export) ClearWeak(w *WeakFields, num pref.FieldNumber) {
+	delete(*w, int32(num))
+}
+
+func (Export) GetWeak(w WeakFields, num pref.FieldNumber, name pref.FullName) pref.ProtoMessage {
+	if m, ok := w[int32(num)]; ok {
+		return m
+	}
+	mt, _ := protoregistry.GlobalTypes.FindMessageByName(name)
+	if mt == nil {
+		panic(fmt.Sprintf("message %v for weak field is not linked in", name))
+	}
+	return mt.Zero().Interface()
+}
+
+func (Export) SetWeak(w *WeakFields, num pref.FieldNumber, name pref.FullName, m pref.ProtoMessage) {
+	if m != nil {
+		mt, _ := protoregistry.GlobalTypes.FindMessageByName(name)
+		if mt == nil {
+			panic(fmt.Sprintf("message %v for weak field is not linked in", name))
+		}
+		if mt != m.ProtoReflect().Type() {
+			panic(fmt.Sprintf("invalid message type for weak field: got %T, want %T", m, mt.Zero().Interface()))
+		}
+	}
+	if m == nil || !m.ProtoReflect().IsValid() {
+		delete(*w, int32(num))
+		return
+	}
+	if *w == nil {
+		*w = make(weakFields)
+	}
+	(*w)[int32(num)] = m
+}