ref(registry): remove confd check script

In older versions of confd, if a key did not exist then confd would
write out "<no value>" to the template. In confd 0.8 it will just
error out of the key is not found, so this check is no longer necessary.

Author: Matthew Fisher

registry/bin/check

@@ -9,5 +9,4 @@ keys = [
   "/deis/registry",
   "/deis/store/gateway",
 ]
-check_cmd = "/app/bin/check {{ .src }}"
 reload_cmd = "/app/bin/reload"