New menus: beatmap options (erase scores/delete), delete beatmaps (single/all), reload songs.
- Pressing F3 or right-clicking in the song menu state will open the beatmap options menu.
- Pressing F5 in the song menu now opens a confirmation menu before reloading beatmaps.
- Deleted MainMenuExit state, which is replaced by MenuState.EXIT in ButtonMenu.
- Decreased Utils.FONT_XLARGE size (to fit in buttons).
Note: as of 800014e, song directory deletion is broken.
Signed-off-by: Jeffrey Han <itdelatrisu@gmail.com>
