Nicer than having Channel poke it explicitly.

Since changing to events we need to fire when changing from
unknown->away. Before, this was handled by the Server being
told about the new message (and then firing listeners).

Fixes #391.

Fixes #392

If we can't display any lines, there's not much point carrying on.

Most use logic we don't wrap yet :-/

Removes some usages of server.parseHostMask which needs to die.

For now this is just a straight(ish) copy of the way Server worked.
Need to make it use events in the future which should simplify it
quite a bit.

Remove them from the Connection interface.

Will remove them from Connection shortly. Then the functionality
can be pulled out of Server into a sane, separate class.

We now need it to exist independently of anything requesting it,
otherwise we miss lines being added.

This, uh, breaks some channels a little. Will fix in a follow-up.

Add support for Optionals in the event property manager.

Group them by function so the file is a bit easier to navigate.
Use nice syntax for multi-line topic format.

Also add function to do bracketed crazyness for events with reasons.

This isn't used in the UI, and doesn't need to exist with the
individual setter methods.