Per discussion from https://git.opendaylight.org/gerrit/#/c/12898/2/scripts/jjb-autoupdate-project.py

It would be nice to have a file that allows projects to define some variables that the JJB autoupdater can use to replace the defaults.

"For example some projects use develop instead of master as their primary branch and we may want to specify cross-project dependencies."

We would have to clearly define what variables would be useful to be configured.