Use stdlib functions for hash key discovery

When fiddling around with server names in the configuration, you'd have
to do a clean sweep of the whole configuration to ensure that there are
no problems with the fact existence and the ordering.

Using dig (and has_key for compatibility reasons to not change anything
front-facing), we can avoid this problem.

Author: towo

manifests/deploy/export.pp

@@ -18,8 +18,8 @@
   -> Openvpn::Client[$name]
   -> Openvpn::Deploy::Export[$name]
 
-  if $facts['openvpn'] {
-    if $facts['openvpn'][$server][$name] {
+  if has_key($facts, 'openvpn') {
+    if dig44($facts, ['openvpn', $server, $name], false) {
       $data = $facts['openvpn'][$server][$name]
 
       @@file { "exported-${server}-${name}-config":