Added CONTRIBUTING.md file.
Added CONTRIBUTING.md file.

snikch/jquery.dirtyforms,GerHobbelt/jquery.dirtyforms,ziykon/jquery.dirtyforms,snikch/jquery.dirtyforms,NightOwl888/jquery.dirtyforms,snikch/jquery.dirtyforms,ziykon/jquery.dirtyforms,ziykon/jquery.dirtyforms,NightOwl888/jquery.dirtyforms,GerHobbelt/jquery.dirtyforms,NightOwl888/jquery.dirtyforms,GerHobbelt/jquery.dirtyforms