Misc. bug fixes and improvements.
- Fixed Game not loading OsuFile for maps in a song group. (blame: 5612336)
- Implemented rotations for reverse arrows, and added a new one by Alic1a.
- "Auto" mod: pausing no longer requires click to unpause, and mod images are permanently drawn.
- Program now loads from Main Menu instead of Options (unnecessary complications for the sake of a transition).

Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>