Add set-phase-on-sync-enable.  Fails because internal buffer is always marching forward
Try to sync phase when enabling sync follower
Sync phase in more situations.
Make programatically-triggered phase syncing happen inside enginebuffer to prevent off-by-one-buffer misalignment.
Address notes
Merge branch 'master' of github.com:mixxxdj/mixxx into mastersync-sync-phase-on-enable
Don't need to fetchandstore the sync phase flag.
Merge branch 'mastersync-sync-phase-on-enable'

Conflicts:
	src/engine/enginebuffer.cpp
	src/engine/sync/syncable.h