Removed profile.py, moved its functionality into __init__.py

-To profile Invasodado, run the game with 'profile' on the command line
Improved documentation and variable naming in some places

-Not too much logic has actually been modified
-Moved some long contructs to several lines
-Prepended "_" to some variables to enforce privateness
-Made some constants ALL_CAPS
-Documented core.__init__ and game.__init__