Merge pull request #1243 from grindhold/master

Fixed hotspot of hand-cursor
implemented solo-buttons for FxMixer - resolving #1211
coding style fixes
Merge pull request #1248 from grindhold/fxmixersolo

implemented solo-buttons for FxMixer - resolving #1211
Merge branch 'master' of https://github.com/lmms/lmms