Needs moar toolbars.
page-core js libs:
	remove Aloha Editor dependency. 
	contentEditable support for editing blocks into localStorage
Modified configuration for assetic.
Changed required version for JMSSerializerBundle.
Assetic filter changes in base template
ContainerAdmin class (Sonata) now properly refactored as BlockAdmin (finally!).
ContainerAdmin class (Sonata) now properly refactored as BlockAdmin (finally!).
ContainerAdmin class (Sonata) now properly refactored as BlockAdmin (finally!).