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/github.com/google/go-cmp/cmp/compare.go

@@ -6,6 +6,10 @@
 //
 // This package is intended to be a more powerful and safer alternative to
 // reflect.DeepEqual for comparing whether two values are semantically equal.
+// It is intended to only be used in tests, as performance is not a goal and
+// it may panic if it cannot compare the values. Its propensity towards
+// panicking means that its unsuitable for production environments where a
+// spurious panic may be fatal.
 //
 // The primary features of cmp are:
 //
@@ -86,6 +90,52 @@ import (
 // If there is a cycle, then the pointed at values are considered equal
 // only if both addresses were previously visited in the same path step.
 func Equal(x, y interface{}, opts ...Option) bool {
+	s := newState(opts)
+	s.compareAny(rootStep(x, y))
+	return s.result.Equal()
+}
+
+// Diff returns a human-readable report of the differences between two values.
+// It returns an empty string if and only if Equal returns true for the same
+// input values and options.
+//
+// The output is displayed as a literal in pseudo-Go syntax.
+// At the start of each line, a "-" prefix indicates an element removed from x,
+// a "+" prefix to indicates an element added to y, and the lack of a prefix
+// indicates an element common to both x and y. If possible, the output
+// uses fmt.Stringer.String or error.Error methods to produce more humanly
+// readable outputs. In such cases, the string is prefixed with either an
+// 's' or 'e' character, respectively, to indicate that the method was called.
+//
+// Do not depend on this output being stable. If you need the ability to
+// programmatically interpret the difference, consider using a custom Reporter.
+func Diff(x, y interface{}, opts ...Option) string {
+	s := newState(opts)
+
+	// Optimization: If there are no other reporters, we can optimize for the
+	// common case where the result is equal (and thus no reported difference).
+	// This avoids the expensive construction of a difference tree.
+	if len(s.reporters) == 0 {
+		s.compareAny(rootStep(x, y))
+		if s.result.Equal() {
+			return ""
+		}
+		s.result = diff.Result{} // Reset results
+	}
+
+	r := new(defaultReporter)
+	s.reporters = append(s.reporters, reporter{r})
+	s.compareAny(rootStep(x, y))
+	d := r.String()
+	if (d == "") != s.result.Equal() {
+		panic("inconsistent difference and equality results")
+	}
+	return d
+}
+
+// rootStep constructs the first path step. If x and y have differing types,
+// then they are stored within an empty interface type.
+func rootStep(x, y interface{}) PathStep {
 	vx := reflect.ValueOf(x)
 	vy := reflect.ValueOf(y)
 
@@ -108,33 +158,7 @@ func Equal(x, y interface{}, opts ...Option) bool {
 		t = vx.Type()
 	}
 
-	s := newState(opts)
-	s.compareAny(&pathStep{t, vx, vy})
-	return s.result.Equal()
-}
-
-// Diff returns a human-readable report of the differences between two values.
-// It returns an empty string if and only if Equal returns true for the same
-// input values and options.
-//
-// The output is displayed as a literal in pseudo-Go syntax.
-// At the start of each line, a "-" prefix indicates an element removed from x,
-// a "+" prefix to indicates an element added to y, and the lack of a prefix
-// indicates an element common to both x and y. If possible, the output
-// uses fmt.Stringer.String or error.Error methods to produce more humanly
-// readable outputs. In such cases, the string is prefixed with either an
-// 's' or 'e' character, respectively, to indicate that the method was called.
-//
-// Do not depend on this output being stable. If you need the ability to
-// programmatically interpret the difference, consider using a custom Reporter.
-func Diff(x, y interface{}, opts ...Option) string {
-	r := new(defaultReporter)
-	eq := Equal(x, y, Options(opts), Reporter(r))
-	d := r.String()
-	if (d == "") != eq {
-		panic("inconsistent difference and equality results")
-	}
-	return d
+	return &pathStep{t, vx, vy}
 }
 
 type state struct {
@@ -352,7 +376,7 @@ func detectRaces(c chan<- reflect.Value, f reflect.Value, vs ...reflect.Value) {
 // assuming that T is assignable to R.
 // Otherwise, it returns the input value as is.
 func sanitizeValue(v reflect.Value, t reflect.Type) reflect.Value {
-	// TODO(dsnet): Workaround for reflect bug (https://golang.org/issue/22143).
+	// TODO(≥go1.10): Workaround for reflect bug (https://golang.org/issue/22143).
 	if !flags.AtLeastGo110 {
 		if v.Kind() == reflect.Interface && v.IsNil() && v.Type() != t {
 			return reflect.New(t).Elem()
@@ -362,6 +386,7 @@ func sanitizeValue(v reflect.Value, t reflect.Type) reflect.Value {
 }
 
 func (s *state) compareStruct(t reflect.Type, vx, vy reflect.Value) {
+	var addr bool
 	var vax, vay reflect.Value // Addressable versions of vx and vy
 
 	var mayForce, mayForceInit bool
@@ -383,6 +408,7 @@ func (s *state) compareStruct(t reflect.Type, vx, vy reflect.Value) {
 				// For retrieveUnexportedField to work, the parent struct must
 				// be addressable. Create a new copy of the values if
 				// necessary to make them addressable.
+				addr = vx.CanAddr() || vy.CanAddr()
 				vax = makeAddressable(vx)
 				vay = makeAddressable(vy)
 			}
@@ -393,6 +419,7 @@ func (s *state) compareStruct(t reflect.Type, vx, vy reflect.Value) {
 				mayForceInit = true
 			}
 			step.mayForce = mayForce
+			step.paddr = addr
 			step.pvx = vax
 			step.pvy = vay
 			step.field = t.Field(i)