fix js errors, fixes #968

resources/assets/javascripts/bootstrap/actionmenu.js

resources/assets/javascripts/bootstrap/application.js

resources/assets/javascripts/bootstrap/article.js

resources/assets/javascripts/bootstrap/avatar.js

resources/assets/javascripts/bootstrap/blubber.js

resources/assets/javascripts/bootstrap/cache-admin.js

resources/assets/javascripts/bootstrap/copyable_links.js

resources/assets/javascripts/bootstrap/files.js

resources/assets/javascripts/bootstrap/forms.js

resources/assets/javascripts/bootstrap/fullcalendar.js

resources/assets/javascripts/bootstrap/inline-editing.js

resources/assets/javascripts/bootstrap/installer.js

resources/assets/javascripts/bootstrap/mvv_difflog.js

resources/assets/javascripts/bootstrap/raumzeit.js

resources/assets/javascripts/bootstrap/resources.js

resources/assets/javascripts/bootstrap/responsive.js

resources/assets/javascripts/bootstrap/search.js

resources/assets/javascripts/bootstrap/sidebar.js

resources/assets/javascripts/bootstrap/statusgroups.js

.../assets/javascripts/bootstrap/studip_helper_attributes.js