[Freeciv] new ranking demo

[Horn Gábor <Horn.Gabor@xxxxxxxxxxx>]

Hi!

I've put a demo from the new ranking to our server: 

http://aktiv.co.hu/~hirisov/civserver/

It's basic yet, but if you click on a player's name you can see some new
things that can be do with it. Now i store complete history for all the
ranked players, not only the current (last) state.

The database is calculated with the new script from gamelogs of games
#43027-#233550. As i've almost fisihed it, i write a short changelog of
it:

- it handles AI and dead (tv) players properly, none of them affects
ranking of players. So now the system is closed and the average of
ranking points is 1000 always (as it's supposed to be in an ELO-like
system)
- it recognizes better (well, i hope all of) the gamelogs it cannot
parse, and ignore them (unlike the current which loads corrupt data to
the base in such cases)
- it recognizes type of game, so no need for separated ranking
databases, all type can be stored in one table and we can choose later
if wanna different rankings for different types (ffa, team, duel)
- it saves all the player's ranking data after every game into a
separated table, so some nice post processing might will be available
- it recognizes and handles alliances in the game (as described at
http://lists.complete.org/freeciv@xxxxxxxxxxx/2003/10/msg00051.html.gz)
- optionally it can resolve chain alliances (this needs further
investigation)

I know about 1 more thing that has to be implemented to be closer to the
ELO, and that's the decay - so if a player doesn't play for a specified
time, we gradually start to move his ranking to the average (so increase
if under 1000 and decrease if above that) as we have less info about
him, so have to assume he's "average" (ELO assumes all the unknown/new
players to be average). It's not a hard thing, i'll do it soon.

And about chain allies: i'd need advice what to do w/ them. Ignore them?
Automatically resolve them always? Only resolve if the members of chain
attacks the same countries, and never each other (so behave like a real
ally), or something else?

bye, hirisov