Removed some more compiler warnings from Windows compile (GCC 4.4).

Added -Wextra to the Windows compile.
Added new define in libbitdht for snprintf and fprintf to proper handling of "%ll" under Windows.

git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@4951 b45a01b8-16f6-495d-af2f-9b41ad6348cc

libretroshare/src/upnp/UPnPBase.cpp

@@ -955,6 +955,9 @@ m_WanService(NULL)
 #ifdef UPNP_DEBUG
 	std::cerr << "UPnPControlPoint::CUPnPControlPoint() bound to " << ipAddress << ":" <<
 		port << "." << std::endl;
+#else
+	// unused variable
+	(void)port;
 #endif
 
 	ret = UpnpRegisterClient(