Update installation.rst
Update installation.rst

Changed class destination
bgaleotti/SonataMediaBundle,nicolasricci/SonataMediaBundle,vyshkant/SonataMediaBundle,nicolasricci/SonataMediaBundle,OskarStark/SonataMediaBundle,sonata-project/SonataMediaBundle,bgaleotti/SonataMediaBundle,nicolasricci/SonataMediaBundle,bgaleotti/SonataMediaBundle,bgaleotti/SonataMediaBundle,Soullivaneuh/SonataMediaBundle,Soullivaneuh/SonataMediaBundle,vyshkant/SonataMediaBundle,vyshkant/SonataMediaBundle,Soullivaneuh/SonataMediaBundle,hug963/SonataMediaBundle,vyshkant/SonataMediaBundle,nicolasricci/SonataMediaBundle,Soullivaneuh/SonataMediaBundle,rmzamora/SonataMediaBundle,OskarStark/SonataMediaBundle,jerome-fix/SonataMediaBundle,OskarStark/SonataMediaBundle,vyshkant/SonataMediaBundle,OskarStark/SonataMediaBundle,hug963/SonataMediaBundle,Soullivaneuh/SonataMediaBundle,nicolasricci/SonataMediaBundle,jerome-fix/SonataMediaBundle,jerome-fix/SonataMediaBundle,hug963/SonataMediaBundle,rmzamora/SonataMediaBundle,hug963/SonataMediaBundle,rmzamora/SonataMediaBundle,hug963/SonataMediaBundle,jerome-fix/SonataMediaBundle