check fastest mirror

[Auke Kok]

just a suggestion, but would a topological field in the mirror list be helpful?

we can -for instance- say for each mirror whether it is in one of the following 
regions:

NAW - North America West
NAE - North America East
SAM - South America
EUW - Europe West
EUE - Europe East
APW - Asia Pacific West
APE - Asia Pacific East
ARB - Arab region
AFN - Africa North
AFS - Africa South
AUS - Australia

any subdivision further is meaningless as the internet is not clustered more 
than this (I think).

It would be trivial to add weights to servers within this region for the 
preprogrammed mirrors and have the user enter a single region preference (hell 
we could even use dvd-region numbers :)).

I think any more specific selection of mirrors would be futile, the lunar code 
can handle fallback already prettu good so this could be a simple solution and 
doesn't require a tool to discover faster/smarted servers.

Auke