Merge pull request #133 from fritsch/hammer

ActiveAE: Fix compilation on non __SSE__ platforms
ActiveAE: stream fixes
ActiveAE: more fixes
ActiveAE: one more non sse
ActiveAE: xfade fix
ActiveAE: another xfade fix
AE: allow to register audio callback directly into engine
ActiveAE: xfade fixes
ActiveAE: mute, volume
ActiveAE: Fix SetVolume by sending the correct message