[autotest] Move database configuration to separate file.

As we're about to add more databases the logic for parsing the
database configurations gets more complicated.

This centralizes the configuration parsing in one dedicated file.

BUG=chromium:419435
DEPLOY=apache,scheduler,host_scheduler,shard_client
TEST=Ran suites, tried syncdb and apache restart

Change-Id: I486b72f30ccd0f1e44316927b4fe3d5c93eacbe2
Reviewed-on: https://chromium-review.googlesource.com/223377
Reviewed-by: Dan Shi <dshi@chromium.org>
Commit-Queue: Jakob Jülich <jakobjuelich@chromium.org>
Tested-by: Jakob Jülich <jakobjuelich@chromium.org>
5 files changed