introduced a proper half open TCP connection limit. Also exposed the connection queue to let clients use the same connection limiter as libtorrent. UPnP connections and tracker connection are now also limited as well as peer connections and web seeds

src/tracker_manager.cpp

@@ -481,6 +481,7 @@ namespace libtorrent
 
 	void tracker_manager::queue_request(
 		asio::strand& str
+		, connection_queue& cc
 		, tracker_request req
 		, std::string const& auth
 		, address bind_infc
@@ -507,6 +508,7 @@ namespace libtorrent
 			{
 				con = new http_tracker_connection(
 					str
+					, cc
 					, *this
 					, req
 					, hostname