jquery: update to jQuery v2.1.1
fix: messages are being parsed over and over again

Because the script never detected that div already had the
gcolordiff-message class set, it parsed the same messages over and over
again. Every time it was set as a matching message, it would 'reappear'
and be parsed again.
Merge pull request #1 from jasperboot/master

fix for broken reparsing + update to latest jQuery