implements a beautiful new way to use learn

$val=$this->learn('val_cache', expensive_callback);
Allow specifying different combination of field groups
Allow place objects in the middle of elements of certain type (views)
derestrict access
when popover is inside dialog, don't tear of title of the original dialog
Allow use of JavaScript in regular menu
Upgrade jQuery -> 1.9.1 and, jQuery UI 1.10.1