Merge pull request #24 from cyoung/ahrs_dev

Fix nil pointer dereference crash.

main/managementinterface.go

@@ -276,13 +276,13 @@ func handleSettingsSetRequest(w http.ResponseWriter, r *http.Request) {
 						globalSettings.GPS_Enabled = val.(bool)
 					case "IMU_Sensor_Enabled":
 						globalSettings.IMU_Sensor_Enabled = val.(bool)
-						if !globalSettings.IMU_Sensor_Enabled {
+						if !globalSettings.IMU_Sensor_Enabled && globalStatus.IMUConnected {
 							myIMUReader.Close()
 							globalStatus.IMUConnected = false
 						}
 					case "BMP_Sensor_Enabled":
 						globalSettings.BMP_Sensor_Enabled = val.(bool)
-						if !globalSettings.BMP_Sensor_Enabled {
+						if !globalSettings.BMP_Sensor_Enabled && globalStatus.BMPConnected {
 							myPressureReader.Close()
 							globalStatus.BMPConnected = false
 						}