AUTH-2587 add config watcher and reload logic for access client forwarder

watcher/notify.go

@@ -0,0 +1,14 @@
+package watcher
+
+// Notification is the delegate methods from the Notifier
+type Notification interface {
+	WatcherItemDidChange(string)
+	WatcherDidError(error)
+}
+
+// Notifier is the base interface for file watching
+type Notifier interface {
+	Start(Notification)
+	Add(string) error
+	Shutdown()
+}