suite names

[Matt Kraai <kraai@alumni.cmu.edu>]

Howdy,

To fix bug 148606, I'd like to change choose-mirror and
cdrom-detect to use stable, testing, and unstable instead of sarge
and sid.

I'll also need to change base-installer to retrieve the Release
file and use it to determine the suite code name for debootstrap.

Any objections?

Matt