fixing bug #4493
subscribers of taxonomy are no more immediately notified when new contribution is created
fixing bug #4372
fixing bug #4497
fixing bug #4499
closing bug #4372
closing bug #4497
fixing bug #4506
Furthermore, description on folders is no more mandatory
components #5.11.x :  Merge branch 'bugs-20130419' into components-5.11.x
fixing bug #4518 by escaping String