rem debug in extensions

git-svn-id: http://music21.googlecode.com/svn/trunk@3718 5c16147e-a200-11de-b0cc-ab0ad15e60d0
Improved documentation examples.

testDocumentation now passes completely.


git-svn-id: http://music21.googlecode.com/svn/trunk@3719 5c16147e-a200-11de-b0cc-ab0ad15e60d0