Removed old documentation in music21 (not music21base)

git-svn-id: http://music21.googlecode.com/svn/trunk@3544 5c16147e-a200-11de-b0cc-ab0ad15e60d0
Removed old buildDoc 

git-svn-id: http://music21.googlecode.com/svn/trunk@3545 5c16147e-a200-11de-b0cc-ab0ad15e60d0
Exempted some docs, moved nbconvert

git-svn-id: http://music21.googlecode.com/svn/trunk@3546 5c16147e-a200-11de-b0cc-ab0ad15e60d0
added forceDifflib to search/segment.

git-svn-id: http://music21.googlecode.com/svn/trunk@3547 5c16147e-a200-11de-b0cc-ab0ad15e60d0