re #4375 better animation

git-svn-id: svn://develop.studip.de/studip/trunk@31131 c5b85792-5220-0410-ad23-ed5b6b8ad999
documents: only number files if title is set during upload, otherwise fall back to filename, re #4235, re #4500

git-svn-id: svn://develop.studip.de/studip/trunk@31132 c5b85792-5220-0410-ad23-ed5b6b8ad999