coreos-base/oem-rackspace-teeth: Make cloudinit drop-in an actual unit

This will guarentee that cloudinit reloads systemd's unit files.
Also, fix the ordering on the config-drive mount.

sdk_container/src/third_party/coreos-overlay/coreos-base/oem-rackspace-teeth/files/cloud-config.yml

@@ -1,23 +1,20 @@
 #cloud-config
 
-write_files:
-    - path: /run/systemd/system/user-configdrive.service.d/netconf.conf
-      permissions: 0644
-      content: |
-        [Service]
-        ExecStart=
-        ExecStart=/usr/bin/coreos-cloudinit --from-configdrive=/media/configdrive --convert-netconf=debian
-
 coreos:
     units:
+      - name: user-configdrive.service.d/netconf.conf
+        runtime: yes
+        content: |
+          [Service]
+          ExecStart=
+          ExecStart=/usr/bin/coreos-cloudinit --from-configdrive=/media/configdrive --convert-netconf=debian
       - name: media-configdrive.mount
         command: start
         runtime: yes
         content: |
           [Unit]
-          DefaultDependencies=no
-          Conflicts=umount.target
-          Before=local-fs.target umount.target
+          Wants=user-configdrive.service
+          Before=user-configdrive.service
 
           [Mount]
           What=/dev/disk/by-label/config-2