Cleans up a lot of code, removes handles for now.
Also adds variant to settings
Fixes https://github.com/ppy/osu/issues/1625 .
Fixes #1911. This follows what osu!stable does, which is rather unfortunate, since it just plays _every_ sound for the note :|.
# Conflicts: # osu.Game.Rulesets.Mania/UI/ManiaPlayfield.cs # osu.Game/Rulesets/UI/Playfield.cs
Player checks for HasReplayLoaded in Player.load(), but the replay is attached in ReplayPlayer.LoadComplete(), which is too late.