Orientation sample updates

I updated the orientation sample to:
* Allow for switching between filtered and unfiltered mode.  This made
  for a better demo of the impact of low-pass filtering.
* I also added code which counts the number of samples and every 10
  seconds it dumps the samples/sec count to the Processing console.
Add stats to filterPlay sample

The filterPlay sample now calculates the mean and variance for each
sensor axis and dumps them to the Processing console every ~10 minutes.