GitLab

Based on pools.cfg in infradata/config. Not really used by anything
yet.

One complication is per-milestone projects: we "fork" builders, but
not Swarming pools. So some chunks of configuration should be defined
only on the main branch.

R=gbeaty@chromium.org, estaab@chromium.org, iannucci@chromium.org
BUG=1123142

Change-Id: I4850e1be0efc6215a0bc58f3ad707dbdc3a1e473
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2401814Reviewed-by: Erik Staab <estaab@chromium.org>
Reviewed-by: Garrett Beaty <gbeaty@chromium.org>
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Vadim Shtayura <vadimsh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806273}