* Begin breaking apart gam.py into logical pieces
Start with one of the deepest parts of the stack, Google API request execution calls and associated errors. Critical information printing functions and application control logic are also broken out into their own components.
This change also adds unit tests for migrated content and makes code more PEP8 compliant.
This commit starts work on jay0lee/GAM#147
* Add unit tests to Travis config
* Swap assert_called_once() with assertEqual() and Mock.call_count
Makes tests compatible with Python 3.5. assert_called_once() is only available in Python 3.6+
