update gomock link to github

README.md

@@ -617,7 +617,7 @@ See [go-hardware](https://github.com/rakyll/go-hardware) for a comprehensive lis
 * Mock
     * [counterfeiter](https://github.com/maxbrunsfeld/counterfeiter) - Tool for generating self-contained mock objects
     * [go-sqlmock](https://github.com/DATA-DOG/go-sqlmock) - Mock SQL driver for testing database interactions
-    * [gomock](https://code.google.com/p/gomock/) - Mocking framework for the Go programming language.
+    * [gomock](https://github.com/golang/mock) - Mocking framework for the Go programming language.
     * [mockhttp](https://github.com/tv42/mockhttp) - Mock object for Go http.ResponseWriter
 
 * Fuzzing and delta-debugging/reducing/shrinking