Merge pull request #1 from stefk/master

Allow compatibility with Symfony 2.3
Searching Questions.
Merge branch 'master' of https://github.com/UJM-dev/ExoBundle.git
Pagination and sort questions
Pagination (uncomplete).
Refactoring
Control the role to add a document
Pagination && Columns sorting.
Navigation pagination and verification label when add documents.
Correction bug access.
Refactoring and not allow display paper.
Start of docimology's Implementation
Correction bug sorting.
add marks'histogram
Merge branch 'master' of https://github.com/UJM-dev/ExoBundle.git
Correction bug add image.
add marks'histogram correction
Merge branch 'master' of https://github.com/UJM-dev/ExoBundle

Conflicts:
	Controller/ExerciseController.php
Refactoring marks' histogram.
Correction don't display 0.