Investigate getting data timestamps from the CPC

[anushadatar]

As discovered in some of the logger data analysis from Feb 2021. there's a pretty unfortunate and unpredictable delay associated with the amount of time it takes for the raspi to record the CPC data; this results in a timestamp mismatch where the timestamps on the CPC and the timestamps on the raspberry pi do not quite line up. This is bad for a few reasons, primarily that it makes it harder to validate timing on discrete events like switching and it also makes it harder to validate that the logger is receiving and storing values as expected. Investigating this issue will require searching through content in the manual and seeing if there's a way to get the CPC timestamp value as well as the raspberry pi timestamp value in the logged data file. If that is not possible, there is likely some other mitigation strategy we should pursue.