cursor themes, XFree86-4.3 and the mouse dialog

[Jonathan Blandford <jrb redhat com>]

Currently the mouse properties dialog has a nice little list to select
the user's cursor.  Unfortunately, this only works with older X servers.
With 4.3 there's a new way of selecting pretty, multi-colored cursors,
leaving the old way basically broken.  I don't want to ship GNOME w/
broken cursors for 2.4.  To fix this, I'm going to have to make some
changes.  While they don't strictly qualify as a feature or UI change,
they are somewhat largish.  

 * Extend the gnome-theme-info code to find cursor themes as well.  This
   should be fairly easy as it's just an extention of the icon code.  On
   the other hand, X has a different search path for icons.

 * Change the capplet to show all found icon themes instead of the
   hardcoded set iff the XCursor extention exists.

 * Add some nice thumbnailing code to the list.

Other Issues:

 * Currently, we have two hardcoded themes at two different sizes.  The
   new cursor code gives us the ability to specify arbitrary cursor
   sizes.  I can avoid the interface change by listing every icon twice,
   first in a regular size, the second time as double sized.
   Alternatively, I can add a 'use large icons' toggle button.

 * Looking on the local drive for the cursors a remote server uses is
   pretty broken.  There could be cursors installed on the local machine
   that X doesn't know about and vice versa.

As an alternate solution, we can do the current trick of installing
specific themes, hardcoding their existence in the capplet, and making
symlinks within the users home directory.  That's the approach I used
for RHL9.  It resulted in a lot of people wondering why they couldn't
set their theme explicitly.  Another possibility (that I don't like) is
to simply hide the control when run on a newer server.

Thoughts?
-Jonathan