Inhibit start of supervisord for nailgun

Starting supervisord starts nailgun app too early
before it is ready to serve requests. It will be
started later in the docker container in the
foreground. This prevents a race condition where
DB upgrade takes place and nailgun is stopped.

Change-Id: Icd27758f00e8f472041eb83019cb89dcb030afd1
Closes-Bug: #1453400

deployment/puppet/nailgun/examples/nailgun-only.pp

@@ -141,6 +141,7 @@ class { "nailgun::client":
   keystone_pass => $::fuel_settings['FUEL_ACCESS']['password'],
 }
 class { "nailgun::supervisor":
+  service_enabled => false,
   nailgun_env     => $env_path,
   ostf_env        => $env_path,
   conf_file       => "nailgun/supervisord.conf.nailgun.erb",

deployment/puppet/nailgun/manifests/supervisor.pp

@@ -1,4 +1,5 @@
 class nailgun::supervisor(
+  $service_enabled = true,
   $nailgun_env,
   $ostf_env,
   $conf_file = "nailgun/supervisord.conf.erb",
@@ -33,8 +34,8 @@ class nailgun::supervisor(
   }
 
   service { "supervisord":
-    ensure => "running",
-    enable => true,
+    ensure => $service_enabled,
+    enable => $service_enabled,
     require => [
                 Package["supervisor"],
                 ],