Move signal hack to BNetworkRequest

* This is used to unlock sockets when a read is pending after a close
* It is not needed on requests that don't use a socket.

headers/os/net/NetworkRequest.h

@@ -22,9 +22,13 @@ public:
 									BUrlContext* context,
 									const char* threadName,
 									const char* protocolName);
+
+	virtual	status_t			Stop();
+
 protected:
 			bool 				_ResolveHostName(uint16_t port);
 
+			void				_ProtocolSetup();
 			status_t			_GetLine(BString& destString);
 
 protected:

headers/os/net/UrlRequest.h

@@ -48,6 +48,7 @@ public:
 
 protected:
 	static	int32					_ThreadEntry(void* arg);
+	virtual	void					_ProtocolSetup() {};
 	virtual	status_t				_ProtocolLoop() = 0;
 	virtual void					_EmitDebug(BUrlProtocolDebugMessage type,
 										const char* format, ...);