[Freeciv-Dev] (PR#2841) categorization of nations

["Jason Short via RT" <rt@xxxxxxxxxxxxxx>]

Here's a new version of the patch.

Changes:

- Don't add a manditory capability.

- Don't hard-code the list of classes in the GUI; instead assemble it as
we go along.  I use an absolute limit of MAX_NUM_ITEMS classes which
results in a large amount of memory used.  However, I consider this
feature pretty essential.

- Use category "Other" at the client end if the nation class is unset;
this will happen if the ruleset doesn't have an entry for it or if the
server doesn't support class_legend.

- Update the patch for current CVS.

I'm not sure if the client/ code should assemble the list of classes, or
leave it up to the GUI.  It's not really any additional work for the GUI
to do it, but it means the nations are in arbitrary order (otherwise we
could put them in alphabetical order).

I'd like to commit the non-gui parts pretty soon.  Vasco: can you look
at the GUI parts?

jason