All mixins take **kwargs

 - **kwargs = location and inventory
Add grammar.py to deal with user action parsing

 - Currently returns tuples of (noun, verb)
Grammar calls getattr on (obj, verb)

 - Still in the process of switching over
 - As opposed to returning tuples

-
Grammar parsing for up to 3-word actions

 - Add grammar.py and tests/grammar_test.py
 - Adds support for adjectives and prepositions in user action input
 - No current support for actions > 3 words
 - Danger of user calling forbidden methods (e.g. __name__)
Update play_game to use new grammar function
Functions standardized to accept location and inv

 - Functions that require a certain parameter (e.g. inventory) set a default value, and raise an exception if that item is not passed in
 - All other functions take **kwargs as a final parameter, so that they can receive (location=location, inventory=inventory) without trouble
Fixed loading a game with a clean DB

 - Previously, trying to load a game where the session id existed but the database had been cleaned threw an error
 - game_site now checks that a session id exists and that the game exists in the DB; otherwise, it will load a new game and create a newsession id