feat(groups/{u,v,w,x}*): vim syntax support

Add vim modeline instructing the editor to use syntax plugin provided by apparmor.
Continuation of #395 to keep the diff list relatively short.

apparmor.d/groups/virt/virtlogd

@@ -44,3 +44,5 @@ profile virtlogd @{exec_path} flags=(attach_disconnected) {
 
   include if exists <local/virtlogd>
 }
+
+# vim:syntax=apparmor