Autotest: Be able to grab the lab status and add it to run_suites

Now that the lab status page is up, we need to be able check when the
lab is not up and in that case stop run_suite from being able to schedule
jobs.

BUG=chromium-os:37095
TEST=Changed the lab status page to lab is closed and ensure that run_suites
     did not schedule the job if that occured.

Change-Id: I0e0f80e872c4b94f5d6148eb5634298ff7263cbc
Reviewed-on: https://gerrit.chromium.org/gerrit/39449
Reviewed-by: Simran Basi <sbasi@chromium.org>
Tested-by: Simran Basi <sbasi@chromium.org>
Commit-Queue: Simran Basi <sbasi@chromium.org>
4 files changed