If there is any deck with sync on, even if stopped, enabling sync on another deck should
not overwrite the master BPM.
TESTED=new unit test that fails with old code, succeeds with new code.
Include inexplicably-missing Xone K2 script file.
More updates to Xone K2 config
Some minor cleanups to WWaveformViewer.
Don't waste time rendering hidden waveform widgets.
Prevent infinite-recursion when changing synchronized zoom on waveforms that share the same group.
Merge branch 'master' into features_effects