rebase: vendor files required for kmip

Signed-off-by: Rakshith R <rar@redhat.com>

vendor/github.com/ansel1/merry/v2/hooks.go

@@ -0,0 +1,37 @@
+package merry
+
+var hooks []Wrapper
+var onceHooks []Wrapper
+
+// AddHooks installs a global set of Wrappers which are applied to every error processed
+// by this package.  They are applied before any other Wrappers or stack capturing are
+// applied.  Hooks can add additional wrappers to errors, or translate annotations added
+// by other error libraries into merry annotations.
+//
+// Note that these hooks will be applied each time an err is passed to Wrap/Apply.  If you
+// only want your hook to run once per error, see AddOnceHooks.
+//
+// This function is not thread safe, and should only be called very early in program
+// initialization.
+func AddHooks(hook ...Wrapper) {
+	hooks = append(hooks, hook...)
+}
+
+// AddOnceHooks is like AddHooks, but these hooks will only be applied once per error.
+// Once hooks are applied to an error, the error is marked, and future Wrap/Apply calls
+// on the error will not apply these hooks again.
+//
+// This function is not thread safe, and should only be called very early in program
+// initialization.
+func AddOnceHooks(hook ...Wrapper) {
+	onceHooks = append(onceHooks, hook...)
+}
+
+// ClearHooks removes all installed hooks.
+//
+// This function is not thread safe, and should only be called very early in program
+// initialization.
+func ClearHooks() {
+	hooks = nil
+	onceHooks = nil
+}