base::dns::cache requires base::daemontools

Make this dependency explicit.

manifests/dns.pp

@@ -6,7 +6,8 @@ class base::dns {
 
 # This class adds a reference to a local DNS caching server.
 class base::dns::cache inherits base::dns {
-  include base::dns::cache_packages
+  include base::daemontools,
+          base::dns::cache_packages
   
   Base::Dns::Resolv_conf[$::fqdn] { dns_cache => true }
 }