Acl management implemented.
Added 'Class not found' log message.
Page access management implemented.
Added action 'show_views' and option 'page_footer' to page acl, for functional demo
Menu items access management implemented.
Added is_acl_controlled option for widget and implemented acces management for widgets.
is_paginated and is_acl_controlled now will be added for all kind of widgets admin form if option is enabled.
Added "GetAllowed" helper.