|SOURCE|
[Common::GameEntity]
* Added GetID to return the unique ID for this game entity
[Common::GameEntityManager]
* Added GetEntityByID, which will return the object in the pointer passed in
[Common::GameplayGameState]
* Removed the Player class
* Replaced all Player functionality by getting the player from the
  GameStateManager (though, in a fixed way, which will be resolved at a later
  date)