retooling
Remove driver from controller
remove initPiece from TetrisGame model - that should take place elsewhere
rename parsePiece to activateTilesFor - makes more sense and reads better
Tetris game can deactivate tiles, given a piece
rename piece.dropOneLevel to piece.downOne for more consistent naming
tetris game can drop a piece, one row
Rename TetrisGame model to Game to reduce redundancy, rename tetrisGame.js file to models.js for clarity
Update changes
Initializer loads the board