syntax
define camo host in deployment envvars
let varnish redirect camo
no cookies on camo

backend shouldn't set them, but, ..
let symfony and forums know about camo
camo hostname
use /favicon.ico for health check on camo

this let us access to /status even when varnish is running
.. camo answers 200 on non-GET requests, so no special probing needed
haproxy: go directly to camo host if varnish down