Lots of fixes (all unrelated to image processing)

* NTP configuration file is now actually included in the repo
* Mounting approach for external drives is now handled differently (via service rather than /etc/fstab
* Telemetered temperatures and voltages are 8-frame averages and are all floats
* Telemetered temperatures and voltages are scaled by 10 and 500, respectively, for increased precision while using Float2B

Merging immediately