Add another sensor data

[hughbris]

As proof of concept and to test that the rest of the app can scale, add data from another simple sensor (either from the sensor hardware or phone handset) to the app. A useful examples would be an accelerometer.

[hughbris]

Lots of sensors have been stripped from original device, though some are likely to be added.

Meantime, we could take accelerometer readings. Not sensors, but we could also record bearing and accuracy from GPS.