3.5.3: Merge pull request #890 from ngodfraind/bugfixes

• Workspace roles now support special characters (prepared stmt)
• The users emails are now displayed properly in the workspace user lists
• The administrator can fill an url for the portfolio tool instead of using the one in the platform
• The desktop calendar can be exported
• The rss reader can handle corrupted xml (https://github.com/claroline/RssReaderBundle/releases/tag/3.0.2)
• Users can be removed from the workspace queue
• Events can be imported on the desktop calendar
• Events can be imported on the workspace calendar (The file was previously always considered empty)
• Importation of resource "text" through migrations is now supported
• Fixing the administration parameters form submission
• A role can be manually set when users are imported with CSV
• Big CSV files don't trigger errors anymore when users are imported through the GUI
• Workspace creation duration time improved (very usefull for massive user CSV imports)