[Bug] LuLu not respect localhost explicit rules

[sky96111]

It was introduced in #55
causing #371 and #430

Staring with 0.9.6, Lulu allow localhost connection by default. And explicit rule to deny application to connect localhost also not work.
It makes firewall becomes pointless when configuring a system proxy, because application with deny rules can always connect to internet through VPN.

Expect:
deny 127.0.0.1 : any port deny localhost : any port should block application to use system proxy

Solution:

• Add option to enable/disable localhost filtering. When enabled with localhost filtering, any address rule should match 127.0.0.1 localhost
• At least, rules with explicit 127.0.0.1 localhost should be respected