Also, don't fetch vCards in rosterHandler. This could be very expensive for
large rosters, instead we'll fetch them when a user comes online.

Additionally:
It's not feasible to get the current user's fullname from a vCard all the time,
so we still get it from the DOM for now.

Also set bare_jid, domain and muc_domain on the xmppchat obj and not the
connection obj.

This was the last thing still using burry.js, so we now have one less
dependency :)

- Use a template to show the day's date.
- Use time element for the date and datetime attr

Roster changes are listened to on the rosterview and the applicable chatbox is
updated.

Custom status messages are now remembered upon page load.

Also removed the need for the appendMessage method.

and do the fetching and sorting when the view is initialized

Specifically handle the case where a chatbox was destroyed, and then opened again.
We still have the view, so we reuse it.

Remove createChatBox from chatboxesview and move the message received listener to chatboxes

Move render, show and message fetching from ChatBoxesViews to ChatBoxView

and get rid of using chatboxesview to control chabox views