How do I lower the priority of a repository?
Including the official backport repository automatically uses a lower
priority than the default 500. How do i have to do this? I've looked into
the documentation of the "Package" file, but I can't find a priority
Even the configuration inside /etc/apt doesn't include a special setting
My goal is to lower the priority of a private repository with backports
lower than the one of jessie-backports (may be 80). I want to use these
packages before the sponsored packages are uploaded to jessie-backports.