Introduce bittorrent related protocol sniffers

* Introduce bittorrent related protocol sniffers

including, sniffers of
1. BitTorrent Protocol (TCP)
2. uTorrent Transport Protocol (UDP)

Signed-off-by: iosmanthus <myosmanthustree@gmail.com>
Co-authored-by: 世界 <i@sekai.icu>

constant/protocol.go

@@ -1,9 +1,10 @@
 package constant
 
 const (
-	ProtocolTLS  = "tls"
-	ProtocolHTTP = "http"
-	ProtocolQUIC = "quic"
-	ProtocolDNS  = "dns"
-	ProtocolSTUN = "stun"
+	ProtocolTLS        = "tls"
+	ProtocolHTTP       = "http"
+	ProtocolQUIC       = "quic"
+	ProtocolDNS        = "dns"
+	ProtocolSTUN       = "stun"
+	ProtocolBitTorrent = "bittorrent"
 )