Merge pull request #51 from n8fr8/master

let's focus on ICS and up
Merge pull request #52 from n8fr8/master

fixes bug in j3m signing for media export
Merge pull request #53 from n8fr8/master

mostly sensor fixes
improving sucker accuracy and basic config
new calculation for bearing
tuning GPS data to ensure we get altitude, bearing if it exists
added logging of nmea data
beginning work on pressure lookup at third party site