re #4484

bugfixing strange exception with plugins

git-svn-id: svn://develop.studip.de/studip/trunk@31086 c5b85792-5220-0410-ad23-ed5b6b8ad999
scm: remove obsolete public/scm.php, fixes #4493

git-svn-id: svn://develop.studip.de/studip/trunk@31087 c5b85792-5220-0410-ad23-ed5b6b8ad999