Bump default god version to 0.13.3.

There is a bug in God which makes it incompatible with ruby 2 until version 0.13.2.  God will keep writing to it's log file until the disk is full.  This seems like a simple change but I did not run the tests as I couldn't figure out how to run them successfully.  You may need to test with older versions which you need to support.  I simply set the god version in the moonshine.yml file (running ruby 2 and rails 3.2.16) but this change may help others in the future.