With a simple "psql service=wanna-build" we can reach the wanna-build
database from release.d.o.  Using that database, we can provide more
detailed "excuses" for why a package will not migrate.

Concretely, I believe this could happen as below:

 * The "britney" wrapper pulls the data from wanna-build and puts
   in a data format understood by britney2.

 * Britney2 optionally consumes the data as a part of writing the
   excuses.

This allows britney2 to remain an "off-line" tool.  Note that the
"britney" wrapper already fetches on-line data (e.g. from the BTS), so
it already depends on network access.

Thanks,
~Niels