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/set/ints.go

@@ -0,0 +1,58 @@
+// 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 set provides simple set data structures for uint64s.
+package set
+
+import "math/bits"
+
+// int64s represents a set of integers within the range of 0..63.
+type int64s uint64
+
+func (bs *int64s) Len() int {
+	return bits.OnesCount64(uint64(*bs))
+}
+func (bs *int64s) Has(n uint64) bool {
+	return uint64(*bs)&(uint64(1)<<n) > 0
+}
+func (bs *int64s) Set(n uint64) {
+	*(*uint64)(bs) |= uint64(1) << n
+}
+func (bs *int64s) Clear(n uint64) {
+	*(*uint64)(bs) &^= uint64(1) << n
+}
+
+// Ints represents a set of integers within the range of 0..math.MaxUint64.
+type Ints struct {
+	lo int64s
+	hi map[uint64]struct{}
+}
+
+func (bs *Ints) Len() int {
+	return bs.lo.Len() + len(bs.hi)
+}
+func (bs *Ints) Has(n uint64) bool {
+	if n < 64 {
+		return bs.lo.Has(n)
+	}
+	_, ok := bs.hi[n]
+	return ok
+}
+func (bs *Ints) Set(n uint64) {
+	if n < 64 {
+		bs.lo.Set(n)
+		return
+	}
+	if bs.hi == nil {
+		bs.hi = make(map[uint64]struct{})
+	}
+	bs.hi[n] = struct{}{}
+}
+func (bs *Ints) Clear(n uint64) {
+	if n < 64 {
+		bs.lo.Clear(n)
+		return
+	}
+	delete(bs.hi, n)
+}