Support --emit-to-logs

[evandbrown]

Feature Request

What challenge are you facing?

We'd like Concourse metrics in our favorite monitoring tool, Stackdriver. Stackdriver supports deriving metrics from log files, and we have a BOSH add on to push logs to Stackdriver.

A Modest Proposal

If we could enable the --emit-to-logs flag on the ATC, we should be able to get useful Concourse metrics in Stackdriver.