Gpsd + Web Auth Cedar Crash fix

[brickbots]

This messy compound PR fixes two issues:

1. Original dongles used in v1 PiFinders never report satellite info. The asynchronous handling in the gps_gpsd code would block waiting for these reports as the GPSD module itself is not asynchronous.

• Switched code back to synchronous and merged satellite and position message handling to avoid blocking for older GPS dongles

2. The cedar detect GRPC calls have a high likelihood of crashing when the web interface shells out to check user credentials. After debugging and investigation with an end user, authentication on the web interface seems to be one of the primary causes of solver crashing.

• Switched auth checking to use the pam module which is a much better solution overall. Hopefully this will prevent whatever is causing the GRPC calls to fail during/after the auth process