changed tag name to correspond to class name

Author: rohit.chaudhri

src/org/opendatakit/sensors/ODKExternalSensor.java

@@ -34,7 +34,7 @@
  */
 public class ODKExternalSensor implements ODKSensor {
 	// logging
-	private static final String LOGTAG = "SensorImpl";
+	private static final String LOGTAG = "ODKExternalSensor";
 
 	private String sensorId;
 	private boolean usingContentProvider;