post_rules improvements

Don't deref ruleset unconditionally in post_rules, it may be null.

post_rules now takes an ipv arg, and it's called twice in bash script
mode.
Several GUI changes/fixes
- several sub windows stays now within main middle window
- after adding ports to or removing ports from service, the service window reloads
	- added edit_service_destroy function
- after adding or removing hosts from group, the group window reload
- rename edit_zone_network title from 'Networks' to 'Network' in top menu (because it's one network)
- added top menu to zones_section_menu_networks with title 'Networks'
  (this was missing and going back from groups, the top menu wasn't updated)