Limit the gps location dot update to 1 Hz max (the typical max rate of a
GPS), I can see it update more frequently than this, which only conflicts
 with pan and zoom gestures if done too often.
reorganized the location update code so that map updates happen at the time the GPSScanner::ACTION_GPS_UPDATED message is received instead of 1 second afterwards.
Reorged to fix an off by 1 second error
Merge pull request #805 from garvankeeley/freq-of-location

Limit the gps location dot update to 1 Hz max