Allow overriding aptly:server:secure

Change-Id: Ic660fa68eb8506a47f18d4642e7a2369948ca923
diff --git a/aptly/server/single.yml b/aptly/server/single.yml
index d5ff8fc..095c396 100644
--- a/aptly/server/single.yml
+++ b/aptly/server/single.yml
@@ -5,6 +5,7 @@
 parameters:
   _param:
     nginx_aptly_server_host: ${linux:network:fqdn}
+    aptly_server_secure: true
   iptables:
     service:
       enabled: true
@@ -71,7 +72,7 @@
   aptly:
     server:
       enabled: true
-      secure: true
+      secure: ${_param:aptly_server_secure}
       gpg_keypair_id: ${_param:aptly_gpg_keypair_id}
       gpg_public_key: ${_param:aptly_gpg_public_key}
       gpg_private_key: ${_param:aptly_gpg_private_key}