show domain name when establishing a new connection

When a new connection is about to be established and the system performs
a dns resolution, we displayed it like this: 9.9.9.9 (www.opensnitch.io)

It added visibility of what was going on, but if you created a rule to
filter by destination host, you were prompted twice to allow firstly the
DNS query, and secondly the TCP connection, which was a bit annoying.

Some users (#5) also asked to display just the domain, so now we only
display the domain name.

daemon/conman/connection.go

@@ -210,11 +210,9 @@ func (c *Connection) parseDirection() bool {
 func (c *Connection) getDomains(nfp *netfilter.Packet, con *Connection) {
 	domains := dns.GetQuestions(nfp)
 	if len(domains) > 0 {
-		con.DstHost = fmt.Sprint(con.DstHost, " (")
 		for _, dns := range domains {
-			con.DstHost = fmt.Sprint(con.DstHost, dns)
+			con.DstHost = dns
 		}
-		con.DstHost = fmt.Sprint(con.DstHost, ")")
 	}
 }