gui/miscsettings_menu.cpp: add option to enable/disable epg scan

src/system/settings.h

@@ -142,6 +142,7 @@ struct SNeutrinoSettings
 	std::string epg_max_events;
 	std::string epg_extendedcache;
 	std::string epg_dir;
+	int epg_scan;
 
 	//network
 	std::string network_ntpserver;