setup srv records for repository mirrors

See http://httpredir.debian.org/ for details.

_http._tcp.fasttrack.debian.net.    IN      SRV     10 1 80 fasttrack.debian.net.
_http._tcp.fasttrack.debian.net.    IN      SRV     10 1 80 mirror.linux.pizza.

But then we will need to add fasttrack.debian.net/debian-fasttrack as well I think (currently our repo is fasttrack.debian.net/debian).

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information