removed some incidences of @ notation in docblocks where they can be mis...

...parsed as annotations

Usage of @ signs in docblocks can be misinterpreted as annotations, e.g. when having enabled expressions using the JMSSecurityExtraBundle in a Symfony2 app.  This commit removes @ signs that can cause a problem.  (Another option would be to use @IgnoreAnnotation declarations.)

(It may be this is unnecessary, but I am not sure what the best way of preventing this misinterpretation is - whether this is a bug in the JMSSecurityExtraBundle, for example.)