updated geometry -- much better

git-svn-id: http://music21.googlecode.com/svn/trunk@3354 5c16147e-a200-11de-b0cc-ab0ad15e60d0
more improvements for partStaffs

git-svn-id: http://music21.googlecode.com/svn/trunk@3355 5c16147e-a200-11de-b0cc-ab0ad15e60d0