initial support for icmp errors in the DHT

include/libtorrent/kademlia/dht_tracker.hpp

@@ -90,6 +90,7 @@ namespace libtorrent { namespace dht
 		// translate bittorrent kademlia message into the generic kademlia message
 		// used by the library
 		void on_receive(udp::endpoint const& ep, char const* pkt, int size);
+		void on_unreachable(udp::endpoint const& ep);
 
 	private:
 	

include/libtorrent/kademlia/node.hpp

@@ -172,6 +172,7 @@ public:
 	void(std::vector<node_entry> const&)> f);
 	void add_router_node(udp::endpoint router);
 		
+	void unreachable(udp::endpoint const& ep);
 	void incoming(msg const& m);
 
 	void refresh();

include/libtorrent/kademlia/rpc_manager.hpp

@@ -81,6 +81,8 @@ public:
 		, routing_table& table, send_fun const& sf);
 	~rpc_manager();
 
+	void unreachable(udp::endpoint const& ep);
+
 	// returns true if the node needs a refresh
 	bool incoming(msg const&);
 	time_duration tick();