Change to deb.debian.org

switch to deb.debian.org from httpredir.debian.org

The deb.debian.org method may be a better one than httpredir:

. deb.debian.org is maintained much more reliably than httpredir

. httpredir is backed by the mirror network; deb.d.o is by a CDN

. httpredir redirects to the mirror network. deb.d.o is a cache that sits in front of ftp.d.o (and security, and debug, and ports)

. one potential disadvantage: deb.d.o's CDN is a commercial service (fastly) that donates its traffic to debian

. in stretch and later, apt uses the SRV records of deb.d.o to find places instead of HTTP redirects

. local peering arrangements of fastly are likely to result in mirror choices that are more local (and thus faster) to the machine

Peering arrangements for the deb.d.o CDN can be seen here: https://www.peeringdb.com/asn/54113

(from redmine: created on 2016-08-04, closed on 2016-08-04)