[Gtkradiant] first impressions on gtkradiant for wolfenstein on linux

[Hydra]

> When starting gtkradiant for wolf (after creating games/wolf.game) the
> textures radiant/notex and radiant/shadonotex are missing. I think we
> need setup/data/main/ with a pk3 that contains those files. And then the
> setup program has to know about that. setup/linux/setup.data/setup.xml:

Ideally radiant should have it's own internal bitmap which can be overridden
by an external "notex" image on a per-game basis, but for now each game
pack needs it's own "notex" image in a media file that can be read by the
plugins that come with the game-pack.

For example:
vfswad (the halflife .wad file reader) replaces the vfspk3 plugin and thus
can't handle .pk3 files.  The image plugin module is also replaced for
halflife support and the new hlimage module *only* understands hlw files
(the images in .wad files).

For the halflife game-pack I intend to include radiant.wad which contains a
"notex" image.

Also, some older games don't use textures from paths, so "radiant/notex"
doesn't mean anything to halflife which means the shader names
"radiant/notex" and "radiant/shadernotex" need to be per-game specific too.

if you want to take a look at the current halflife support then check out
bug 197 on bugzilla:
http://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=197

For multiple game support we really must consider all the old games and what
any changes would mean to any developer that's writing plugins for them.

Hydra