Added img directory to assets.

Also added stage-changing buttons and the cutting stage background.
Removed unused import from RopGame.

Signed-off-by: Ken Hoover <ken.hoover@mail.utoronto.ca>
Added test font, couple actual changes.

Committing everything, moving to different computer.

Signed-off-by: Ken Hoover <ken.hoover@mail.utoronto.ca>