dialogs: disable button on click, re #4404, re #4497

git-svn-id: svn://develop.studip.de/studip/trunk@32020 c5b85792-5220-0410-ad23-ed5b6b8ad999
documents: use and verify stud.ip tickets as well as crsf protection tags, fixes #4497

git-svn-id: svn://develop.studip.de/studip/trunk@32021 c5b85792-5220-0410-ad23-ed5b6b8ad999