sniffing early work

use `tun` crate examope for starters, to map all traffic through tun
virtual interface, in next commits will push these packets to sniffing
module which will deciede further modifications of proxies based by
user's Config.

src/sniffing/headers.rs

@@ -0,0 +1 @@
+// Here we will recieve bytes and try to get their destanation & apply Rules for them.