edit collaboration
shorten text on p.5 to avoid hyperlink bug

if the 12th footnote (http://lilypondblog.org/2013/11/modifying-already-beautified-scores/)
doesn't fit on one page, the whole first column on the next page gets hyperlinked
together with the footnote (at least on my machine).

Removing a few words should ensure that the footnote stays on one page.
add notes about diffs