[impdev] Merging in magical scripted HUD/UI (msh branch) soon

[Jacek Antonelli]

I'm planning to merge Mm and Admiral's magical scripted HUD/UI work
into my next branch within the next few days, but I'd like to have
some other people try it out before I do.

At the moment, it seems to be some tools for loading (and reloading)
XUI, which is useful for testing when working on UI layouts. There is
also a system for tracing UI events, which will prove useful for the
final feature. I don't think the script <--> UI interaction is
implemented yet (which is okay, because I have some reservations about
using the XUI format anyway).

The code so far is available in my "msh" branch (commit 101b0c1a at
the moment). The new stuff is in the Advanced > XUI menu. Anyone want
to give it a try?

More info:
* http://redmine.imprudenceviewer.org/issues/show/188
* http://jira.secondlife.com/browse/VWR-10924

- Jacek