use URL instead of address for peer
use URL instead of address for peer

Signed-off-by: Chris Brown <85d56cb41a65761dcea36d0ceb2f0ec45f184419@pivotallabs.com>

concourse/concourse,simonjjones/atc,zachgersh/atc,concourse/concourse,utako/atc,savaki/atc,concourse/concourse,pivotal-devin-fallak/atc,pivotal-devin-fallak/atc,utako/atc,simonjjones/atc,concourse/concourse,utako/atc,savaki/atc,zachgersh/atc,zachgersh/atc,pivotal-devin-fallak/atc,simonjjones/atc,savaki/atc,concourse/concourse,zachgersh/atc