jdorje: Restructure nation availability code: - pna...

This is an automated notification of a change to freeciv cvs, 
on Sat Sep  3 21:31:16 PDT 2005 = Sun Sep  4 04:31:16 2005 (GMT)
by Jason Dorje Short <[email protected]>

---- Files affected:

freeciv/client climisc.c packhand.c packhand_gen.c packhand_gen.h
freeciv/client/gui-gtk-2.0 dialogs.c
freeciv/common capstr.c game.c nation.h packets.def packets_gen.c packets_gen.h player.c player.h
freeciv/server barbarian.c citytools.c plrhand.c ruleset.c ruleset.h sanitycheck.c srv_main.c

---- Log message:
      Tag: HEAD

Restructure nation availability code:

- pnation->is_unavailable is renamed as pnation->is_available.
- pnation->is_used is renamed as pnation->player.
- A new function player_set_nation will set (or clear) nations.
- The nation_available packet is removed; availability is sent with the
  regular nation packet.

This also fixes a bug where is_used could get out of sync.

Reported by David Stewart <[email protected]> in PR#13776.  Patch by me.