* Replace hardcoded rainbow effect with UserTier02OrBetterCommand.
* Added Difficulty and Steps param to UpdateNetEvalStats message. The
beginning of custom-themable online stuff begins.
[ScreenNetSelectMusic]
* Started to port SampleMusicPreviewMode from ScreenSelectMusic.
* Changed MusicWheel metrics to read from OnlineMusicWheel instead.
* Added section, roulette, and random music (not used yet).
* Stop the music when reaching a section.
[others]
* some theme file additions
AJ Kelly