* Make sure author cannot reject/approve their own PR
* Disable buttons in templates too
* Remove unneccessary if check since the switch below catches it
* Fix IsOwner check
* Update template and remove new template variable
* Add alert template and redirect to diff page on review failure
* Redirect to files diff as a little update to #4632
* an inactive user shouldn't be able to be a collaborator
* use translated error message
* add active user check when adding a new collaborator via the api
* fix translation text
* added collaborator test
* improvee testcases
* don't fail silently if trying to add a collaborator twice
* fix translation text
* added collaborator test
* improvee testcases
* Added tests to make sure a collaborator cannot be added twice