(PR#10203) Greedy CM algorithm

<URL: http://rt.freeciv.org/Ticket/Display.html?id=10203 >

> [jdorje - Sat Nov 13 06:18:14 2004]:
> 
> I can't say I entirely understand it.  But then the current code is
> even worse.  It does seem pretty clear that the B&B algorithm will
> be a lot less bug-prone than the current method.  So unless anyone
> objects I'll commit this patch (Benoit, make more changes to it if
> you want).
> 
> For S2_0 this is too much of a change, even though it's surely easier
> to debug than the DP algorithm.  So we still want bug fixes for the
> current system.

I beg to disagree. This code is plug-in compatible with the old and
doesn't change the network protocol, i18n strings or anything. It is
totally self-contained in one file (cm.c).

It fixes longstanding bugs and is faster to boot. I think we should
put it in S2_0 now. If it turns out it has even more bugs than the old
one, it is a simple matter of switching it back. Even if this does
happen, we will have got the benefit of increased testing coverage,
which will facilitate its development into a more robust form.