Add chat button to ToolBox.
Add new class cncta.ui.chat.ChatInput.

This class only resembles a widget for getting user input, nothing more at the
moment.
Set window properties for ChatWindow.

Which includes adding the ChatInput widget to the VBox container.
Add missing scrollbar stuff to QX bindings.
Add ChatView class, which represents chat content.

Our chat window now is getting more and more usable, because we can actually see
what we're writing. This currently adds every message from user "foo" with a
timestamp of 00:00:00 and no backend whatsoever, yet.
Refactor chat widget implementation to use ToolBox.

This actually hooks the whole ToolBox instance into CNCTA and adds the window
containers directly by using add_window_button(). In addition this replaces old
cruft from the games chat widget.
Retrieve timestamps from chat messages.

Delayed timestamps from the server are in UTC, so we need to add the UTC time
zone offset. This is somewhat risky, as we are not yet sure if all browsers will
support this. But even when not, they're delayed stamps, so who cares?

If anyone has a more portable solution, don't hesitate to create a pull request.
Get rid of obsolete cruft in xmpp.ChatMessage.

This was only relevant for injecting message types into the C&C TA API, and as
we now have our own chat window, we don't really need this anymore.
Bring to front and center chat win on appearance.
Insert times into chat message lines.
Set chat view minimum width to 300.

Just because 200 is way too small and I get annoyed by resizing it every time
I'm debugging.
Improve the way chat lines are added.

We were using one single Label before, where text was appended by overriding the
value. That way we had to do bookkeeping of two separate variables for the
content and to insert sluggish separators to cut the backbuffer/history.

This now is much much cleaner, as we just use a simple VBox which is filled with
a Label on each line. This is also much cheaper in content.
Get rid of <font/> in chat messages.

Just because <font/> is used in C&C TA doesn't make it legitimate to use by us,
too. So we're replacing it with <span/> and inline CSS.
Add flex and grow values to chat widgets.

This will allow the chat window to be resized correctly and everything within
will fill the space appropriately.
Scroll down chat area if window is resized.
Add new chat nicklist (ChatRoster).

This currently is just a VBox filled with labels, which is enough for now.
The whole nicklist is just to the right of the main chat area, so we might need
to use a split pane here, to make it resizable by the user.
Add/remove members on groupchat enter/leave.

Which means, that it is in a working state right now, so we can see in realtime
when members leave and/or change nicks.

In addition this fixes a small issue, which caused that nickname changes were
seen as "joins" (for the old nick) as XMPP is sending a 303 with the _active_
presence.
Change roster nick colors to yellow.

I know, this may not fit into the design, but first of all: I'm not a designer
and second: It's just to visually separate it from the main chat area.
Merge branch 'chat_nicklist' into chat_window.

Closes #1.
Re-add bbcode parsing to chat view.

We don't want to introduce a regression, do we? ;-)