This fixes situation when there is Original Album but no Album in id3v2 tags (TOAL) and times when there is set band/orchestra but no Artist id3v2 tag (TPE2). We just use those to fill Album and artist because it less wrong than having empty lines in album and artist (which confuses users). This should fix also lauchpad Bug #1266158
When there is an explicit master, make sure rates are instantly communicated
to followers.

Added a unit test that confirms that the tracks remain locked in sync.
make zero latency test more robust
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
Merge branch 'master' into sync-insta-rate
Little bit optimized if version. If there is some album name it's not worth to check originalAlbum name because we don't use it currently elsewhere
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