Added skeletons for TCP/UDP/ICMP packet analysis plugins.

This includes integration into the IP plugin and calling of the sessions code from each plugin.

src/packet_analysis/protocol/udp/UDP.h

@@ -0,0 +1,26 @@
+// See the file "COPYING" in the main distribution directory for copyright.
+
+#pragma once
+
+#include "zeek/packet_analysis/Analyzer.h"
+#include "zeek/packet_analysis/Component.h"
+
+namespace zeek::packet_analysis::UDP {
+
+class UDPAnalyzer : public Analyzer {
+public:
+	UDPAnalyzer();
+	~UDPAnalyzer() override;
+
+	bool AnalyzePacket(size_t len, const uint8_t* data, Packet* packet) override;
+
+	static zeek::packet_analysis::AnalyzerPtr Instantiate()
+		{
+		return std::make_shared<UDPAnalyzer>();
+		}
+
+private:
+
+};
+
+}