Bug#861749: apt-cdrom needs --release option

[Phil Susi <psusi@ubuntu.com>]

Package: apt
Version: 1.2.19

Please add a --release option to apt-cdrom so that it can be asked not
to pick up other releases it finds on the installation medium.

I ask because at least in Ubuntu, we get many thousands of installation
failure reports each year because people reuse the same USB stick to
install another release ( or a different debian based distro ), and
apt-cdrom adds both releases to the sources and apt ends up trying to
pull some packages from one release, and some from another with fire,
death, and explosions ensuing.