Revert "more tests for permissions"

This reverts commit 4169fc807e7516387d15022f7307afcc49040363.
Revert "Merge branch 'develop-js' of github.com:tkowark/hpi-hiwi-portal into develop-js"

This reverts commit b9f77af1419e795287b1a5945a4a9b242c255166, reversing
changes made to 9ba482b81ec571f5c3c3c6212b45fe91b9f816f6.
Revert "implemented tests for permissions"

This reverts commit 9ba482b81ec571f5c3c3c6212b45fe91b9f816f6.
Revert "fixed tests related to visibility issue"

This reverts commit d3a61847ae92501456d14afe4323a4c56cf322ed.
Revert "#80 Student index just visible for wimis (and admins)"

This reverts commit 7c3991ace250745c07a04df72b801731c88f00d5.