Initial work for getting bpm x2 /2 working
Merge branch 'sync-insta-rate' into sync-half-double

Conflicts:
	src/test/enginesynctest.cpp
Double/Half master sync mostly works!
a new unit test for the sync control object.
Start fixing broken tests, uncovering new bugs.
Working out the kinks
Merge branch 'master' into sync-half-double
A lot of work on half/double BPMs, which revealed some bugs in the
testing framework.  And as with the insta-rate change, the internal
clock needs to report its rate before all the buffers have processed,
and report its beat distance afterward.
Remove a whole lot of debug printing.
get rid of warnings
I think things are working ok now?
try to comment out things.  clearly still not working
Fix a problem with beat percentage calculation being off
Merge branch 'sync-insta-rate' into sync-half-double
clean up a few debug prints and comments
Wrap up sync master param setting into one convenience function where possible.
Clean up the diff
More x2 /2 cleanup
one more comment
Merge branch 'sync-insta-rate' into sync-half-double

Conflicts:
	src/engine/bpmcontrol.cpp