* 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
This commit improves templates readability, since all of them use consistent
indent with all template command blocks indented too.
1. Indents both HTML containers such as <div>, <p> and Go HTML template blocks
such as {{if}} {{with}}
2. Cleans all trailing white-space
3. Adds trailing last line-break to each file
