Bug#851099: "auto-apt update" tries to fetch wrong URL

["Phil Endecott" <spam_from_debian_bugs_2017@chezphil.org>]

I think this would have worked in Wheezy, but not since Jessie.

I.e. this is OK:

http://ftp.debian.org/debian/dists/wheezy/Contents-armhf.gz

But since Jessie it needs "main" or whatever between the Debian version
and the "Contents-ARCH.gz" bit:

http://ftp.debian.org/debian/dists/jessie/main/Contents-armhf.gz

Has auto-apt really not worked since Wheezy?

Ah!  Now I see bug #813976 (with the unhelpful title "repair auto-apt"
which proposes splicing "main" into the URL exactly like that.

I'm going to (try to) increase the severity, as it seems that this
package has been broken for years; is no-one using it?