rfalke: Create a new event named E_CITY_PRODUCTION_C...

This is an automated notification of a change to freeciv cvs, 
on Sat Feb  7 03:49:44 PST 2004 = Sat Feb  7 11:49:44 2004 (GMT)
by Raimar Falke <rf13@xxxxxxxxxxxxxxxxx>

---- Files affected:

freeciv/client options.c
freeciv/common capstr.c events.h
freeciv/server citytools.c cityturn.c

---- Log message:
      Tag: HEAD

Create a new event named E_CITY_PRODUCTION_CHANGED which is sent when
the production of a city changes.

Rename the event from E_UNIT_BUILD to E_UNIT_BUILT.

Patch from Jason Short in PR#7232 with changes from me.