We now have a searchBuildsAndEvalsForJobset, which creates such a
mapping for us, so we don't need to duplicate code in jobs_tab and
channels_tab.
Also, we're going to use this for the overview of a particular channel
as well, so it makes sense to put it in CatalystUtils instead of
directly in Jobset.pm.
Instead of eval->jobs, it's now eval->builds, because it's really an
aggregate over the builds schema, rather than the job schema.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
c9aadd8b7d