Log additional environment details at relay startup.
Log additional environment details at relay startup.

Summary:
Realized none of this information was logged earlier when trying to
check out relay issues and figured this would be good information to have in logs.

Reviewers: tail, jeff

Reviewed By: jeff

Differential Revision: http://phabricator.local.disqus.net/D18729

disqus/pgshovel,fuziontech/pgshovel,fuziontech/pgshovel,fuziontech/pgshovel,disqus/pgshovel