modified update.sh

Now only outputs if there were changes, that way my inbox doesn't get flooded.
Merge branch 'master' of github.com:laseut/publications
Merge branch 'master' of github.com:laseut/publications
Merge branch 'master' of github.com:laseut/publications
Merge branch 'master' of github.com:laseut/publications
changed update.sh to look for 'files changed'