This PR adds an automatic gradle format checker and reformats all the *.gradle files. After this, new changes to *.gradle files will fail to build if not in good format, just like checkStyle failure.
Updates include:
* Build file and dependency updates
* Correcting the gradle wrapper for the clientcache example
* Lint fixes (including making AsyncTask subclasses static)
* Dropping the m-prefix from member variables
* Fixing the code indentation
* Fixing and enabling proguard for the routeguide example.