Some PGN Updates I've Collected

These commits (well the three most recent, the others were a) getting caught up with the official canboat repo and b) my screwup with a too-big commit) add a lookup table for temperature source for PGN 130312, correct the pressure and humidity PGNs, and add a bunch of Fusion proprietary PGN definitions. The Fusion PGNs are not complete by any means, but are rather a first pass over what I was able to collect from my stereo.