added properties for querying the game object's position in the screen
created platform class that derives from the Game Object class
Game Object class now implements rect as a property in order to save the half size values for centerx/y queries
added more platforms and made the level larger
renamed the midair dash counter variable to midair_dash_remaining
all game objects now are place relative to the level origin
Merge branch 'master' of https://github.com/jrgnicho/pygame_projects
Merge branch 'level_as_world_frame' into merge_level_to_master
fixed issue with player being moved to the start of the level when the right side of the level was reached
renamed member animation_sprite to drawable sprite in order to stay consistent with the equivalent member used in the platform class