Files can be replaced.
Merge pull request #676 from ngodfraind/replacing-files

Files can be replaced.
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Role list management: name can be changed and roles can be removed.
Adding security for RolesController.
Merge pull request #680 from ngodfraind/updating-role-admin-tool

Updating role admin tool
Small ResourceVoter fix for imporsonation.
Merge pull request #681 from ngodfraind/fixing-rights-when-impersonnating

Small ResourceVoter fix for imporsonation.