merge to master

Change-Id: I71cfcc02362271bb0ff0811b444e0c91e420e4ec
Refactor AFT backend

* New AFT DB schema - once all experimental stuff is gone, AFT data is really simpel
* Build solid feedback model for easier controller implementation
* Remove & refactor lots and lots of pointless and/or abandonned code
* Moved actions-related code into activity class

Change-Id: Iebd886f35baf1f593975342c3c96df5233878e44
New actions, filters & UX

* Change virtually all existing filters
* Change actions "feature" to "useful" and "hide" to "inappropriate"
* Introduce action "non-actionable"
* Change the UX:
  * Now only 1 of the 4 editor tools (useful, resolved, non-actionable, inapropriate) can be performed at once
  * After having flagged on of those 4, "undo" button pops up as well as the details of the previous flag
  * Only after flagging as inappropriate do oversight-related tools pop up
  * Moderation actions are 1-click, with possibility for flyout window to leave comment afterwards

See requirements at http://www.mediawiki.org/wiki/Article_feedback/Version_5/Feature_Requirements#Simpler_moderation_tools

Change-Id: Ibf97654b0d9344fd89e0c8b3377fa821fdc9043f
Bug 42057 - Feedback link on article pages

* Add API endpoint to fetch amount of entries for a given page/filter
* Code for above functionality was in use on special page already; moved that code to utils so both can access this and avoid code duplication
* add Javascript ajax call to fetch the amount of feedback and display a link on article page
* Update talk-page link to also only display if there is feedback

Change-Id: I03c815d8257aaa590ef639387c360d8356cd0d96
Post without comment

Change-Id: I6ece35a9f675acdb38bee48d177ff6ad1cdc4eec
(bug 43419) Remove reader tools for editors in feedback page

Change-Id: I775c215e00b55af50949b8366e62f07295009e7c