Merge remote-tracking branch 'origin/master' into develop
Merge branch 'develop-ja' of https://github.com/tkowark/hpi-hiwi-portal into develop-ja
Merge pull request #154 from tkowark/develop

Merging develop into master to fix production errors
Merge remote-tracking branch 'origin/develop'
Merge branch 'develop' of https://github.com/tkowark/hpi-hiwi-portal
Merge branch 'develop' of https://github.com/tkowark/hpi-hiwi-portal
Merge branch 'develop' of https://github.com/tkowark/hpi-hiwi-portal into develop
#147 promotion of student to staff with dialog and confirmation
Merge pull request #163 from tkowark/develop

Refactorings + Improvements
add form and change mailer for #144
removed footer from dialog
#147 deputy can promote student to deputy
Merge branch 'develop-ja-aquire-role' of https://github.com/tkowark/hpi-hiwi-portal into develop-ja-aquire-role
refactored research_assistant_controller a little + some tests
added two users_controller tests
adjusted some tests
removed unused student factory
made user factory a little more robust regarding status objects
made helper spec a little more flexible. Translation behaviour seems indeed a bit off between programming_language and language
more tests + refactorings, including #165 and #166