Move dircache, oauthutil, rest and pacer modules into lib

lib/oauthutil/oauthutil_old.go

@@ -0,0 +1,16 @@
+// oauthutil parts pre go1.8+
+
+//+build !go1.8
+
+package oauthutil
+
+import "github.com/ncw/rclone/fs"
+
+func (s *authServer) Stop() {
+	fs.Debugf(nil, "Closing auth server")
+	if s.code != nil {
+		close(s.code)
+		s.code = nil
+	}
+	_ = s.listener.Close()
+}