makes the beams look OK on the second draw
adds breve notes
merged with upstream
roll back some beaming changes
adds breve notes as duration 0
breves now duration of 0.5
breve notes use b or 1/2
can't give breves a b duration anymore
changes tests to not use b duration breves
Merge branch 'breve' of https://github.com/ssoRL/vexflow into breve