[freeciv-data] Primary & Secondary sets of nations

[Dmitriy Genzel <udgenzel@xxxxxxxxxxxxxx>]

Given the fact that there are seem to be objections on the ground of
certain nations, and that some are clearly included in others, I suggest
we clearly separate some of the nations into a separate set which is
included in the distribution perhaps, but not available to the user by
default. Another reason to do this is so that the screen won't become
unusably cluttered when choosing a nation.

I don't suggest (yet) that we need to remove any nation that is a nation
in its own right existing today, or a separate nation of great importance
that has disappeared. But, nations like Bavarians, Texans, Dunedain &
Mordor and the like should go into the second set. If Nazis get included
(and I am against that) they should go there too.

Here's a suggestion on rigid criteria. We include a
nation in the first set, only if
1) It is in existense today in the form of a national state
or
2) It has been an ancient civilization that has no clear successor (e.g.
Franks & French) of sufficient importance

I am sure that this cuts off many things we'd like to see, but at least it
is somewhat fair. Anyway, if you like a nation, change the config and use
it on your home computer.

Dmitriy