Commits for review: Add php Error Reporting Functionality to PMA (Rebased)

*In continuation with Pull#1207.*
**Things Done:**
 - [x] Rebasing with upstream. (There were few conflicts which I had to resolve.)
 - [x] Some displayed message improvements.
 - [x] Found & stopped one more false alarm.

**~~Things yet TODO:~~**  *Done now*
 - [x] Remove inline JavaScripts as suggested in [Pull#1207](https://github.com/phpmyadmin/phpmyadmin/pull/1207#discussion_r13531075).

~~Will push **TODO** changes soon.~~ *Done now*

Till then, kindly review other parts. :smiley: 
I don't really like such ambiguity in return value. Why not just return array in all cases. It can be empty in case there are no errors to report.