Ansible playbooks and a few bug fixes

PLEASEREVIEW @jengo @declanshanaghy @edsplunk @nicholaskeytholeong @camgas 
Still to do:  basic auth in front of hydra; ssl in front of hydra

AMI-396 playbook progress

Parameterize some stuff.

AMI-396 fix source upload?

AMI-396 colon cancer

AMI-396 tweaking

AMI-396 configure supervisor

AMI-396 god-damn yaml is fussy

AMI-396 more yaml tweaks

AMI-396 more yaml tweaks

AMI-396 more yaml tweaks

AMI-396 more yaml tweaks

AMI-396 supervisord is just called supervisor

AMI-396 add build number output

AMI-396 install sidecar also

AMI-396 forgot to quote.

AMI-396 yaml sucks

AMI-396 ansible sucks too

AMI-396 change where we output the build number since it's not in json format

AMI-396 prepare for running in AWS

AMI-396 typo, and make more portable

SEC-396 fix a bug where stale entries were not removed from the instances list

AMI-396 remove old services, but don't clear the entire array

AMI-396 fix bug where only a single path would be proxied