Added a form with inputs for the configuration options (not yet usable)

Add a configure button on chatrooms when the user is the chatroom owner.

For now we just create an instant chatroom, but eventually we must provide a
way through the UI in which the user can request to configure the room.

when clicking the info icon next to a room's name

It's way to inefficient when there are multiple chatrooms. Instead, I added an
info icon that can be clicked and which will fetch and display additional info
on the chatroom.

Also make sure that logged in user's fullname is fetched from xmppstatus obj.

So that we can make releases

Inefficient, causes way too much traffic and takes very long

Also show a spinner when logging in (to disable resubmitting login form)
and when refreshing the available chatrooms.

- by using documentFragment