common (jidSelector): replace implitict_update mechanism by real-time update:
instead of having the possibility to (de)activate implicit update, real time update of
items is now done.
For now only the notifications and opened chat items are updated in real time.
13 You can follow this documentation to learn more on it, or join our official XMPP room at `sat@chat.jabberfr.org <xmpp:sat@chat.jabberfr.org?join>`_ (also available via a `web link <https://chat.jabberfr.org/converse.js/sat@chat.jabberfr.org>`_)