Start rewriting pushing logic to use actions
Move from module to package; start action classes
Ignore __pycache__ directories
Enhance comments and rename a few methods
Merge branch 'actions'
Add simple bash script to launch a game easily
Theoretically switch to function-based actions

But Pyglet is broken so I can't test it.
Add setup.py file that installs dev Pyglet
Start porting to PySDL2
Get everything mostly working with PySDL2
Update README to discuss new dependencies
Finish moving to PySDL2
Merge branch 'pysdl2-refactor'
Remove no-longer-needed 'play' script