messages: regard ENABLE_EMAIL_ATTACHMENT setting, fixes #5227

git-svn-id: svn://develop.studip.de/studip/trunk@32941 c5b85792-5220-0410-ad23-ed5b6b8ad999
messages: regard ENABLE_EMAIL_ATTACHMENT setting, fixes #5227

git-svn-id: svn://develop.studip.de/studip/trunk@32942 c5b85792-5220-0410-ad23-ed5b6b8ad999