Refactor family acl

This replaces add/remove attributes acl by a single edit attributes acl that also covers editing the requirements
Create a category reader that sorts categories by tree and order before exporting
Update changelog
Update behat scenario
Prevent multiple concurrent ajax requests on the job execution show page
Add title for system configuration page
[CrowdIn] Updated translations
Fix allowed image extensions in the Behat catalogs
Merge pull request #1410 from akeneo/fix/behat

Fix allowed image extensions in the Behat catalogs
Merge pull request #1400 from akeneo/PIM-2866

Create a category reader that sorts categories before exporting
Merge pull request #1408 from nono-akeneo/crowdin/2014-08-18-04-16

Update translations from CrowdIn
Merge pull request #1407 from akeneo/PIM-2815

PIM-2815 Add title for system configuration page
Merge pull request #1406 from akeneo/PIM-2625

PIM-2625 Prevent multiple concurrent ajax requests on the job execution show page
Merge pull request #1399 from akeneo/PIM-3042

Refactor family acl
PIM-2511 fixes
Merge pull request #1412 from akeneo/fix/PIM-2511

PIM-2511 fixes
Fix category order in the categories tab