Smart Altimeter

Sep 10, 2018

- fixed unintended 2s lag due to excessive smoothing; the lag on devices with fast barometers should not exceed 0.1s now or 12 samples, whichever is greater
- changed number formatting of altitude to resemble skydiving altimeters: altitude is rounded to 10 units if below 1000 units; displayed in thousands with 2 decimals if above 1000 units
- added raw altitude AMSL output, for observing sensor sensitivity and accuracy