jdorje: Fix bugs with dereferencing of T_UNKNOWN, by...

This is an automated notification of a change to freeciv cvs, 
on Thu Jul 21 12:32:03 PDT 2005 = Thu Jul 21 19:32:03 2005 (GMT)
by Jason Dorje Short <[email protected]>

---- Files affected:

freeciv/client helpdata.c packhand.c
freeciv/client/gui-gtk helpdlg.c
freeciv/client/gui-gtk-2.0 helpdlg.c
freeciv/client/gui-win32 helpdlg.c
freeciv/client/gui-xaw helpdlg.c
freeciv/common game.c map.c map.h terrain.c terrain.h
freeciv/server ruleset.c savegame.c
freeciv/server/generator mapgen.c

---- Log message:
      Tag: S2_0

Fix bugs with dereferencing of T_UNKNOWN, by changing such dereferences to
be harmless:
- The tile_types[] array is hidden.  All users are changed to use
  get_tile_type().
- get_tile_type returns a dummy tile_type for T_UNKNOWN references.

Patch by me in PR#13488.