Mirror reorganisation

Change-Id: Ie79627effc6ac18dc6a8093e00dfa79930013fe7
diff --git a/aptly/server/mirror/ubuntu/xenial/ceph.yml b/aptly/server/mirror/ubuntu/xenial/ceph.yml
index efb1703..8972cf2 100644
--- a/aptly/server/mirror/ubuntu/xenial/ceph.yml
+++ b/aptly/server/mirror/ubuntu/xenial/ceph.yml
@@ -1,9 +1,11 @@
 parameters:
+  _param:
+    ceph_version: luminous
   aptly:
     server:
       mirror:
         ceph-xenial:
-          source: http://download.ceph.com/debian-hammer
+          source: http://download.ceph.com/debian-${_param:ceph_version}
           distribution: xenial
           components: main
           architectures: amd64