Add CloudInit step to vsphere agent settings

This allows the agent to fetch settings from cloudinit in vsphere instead of mounting the CD-ROM. Note that this change shouln't be merged until there is a compatible agent binary available.

Author: julian-hj

stemcell_builder/stages/bosh_vsphere_agent_settings/apply.sh

@@ -16,6 +16,8 @@ cat > $chroot/var/vcap/bosh/agent.json <<JSON
     "Settings": {
       "Sources": [
         {
+          "Type": "CloudInit"
+        }, {
           "Type": "CDROM",
           "FileName": "env"
         }