Allow a user-specified list of NMEA2000 PGNs to be recorded as raw bytes for later reporting

[brian-r-calder]

For certain use cases, there ay be other NMEA2000 packets that would provide useful data, but which are currently dropped on the floor by the logger (referencing NMEA2000 logger v 1.1.0) in an attempt to minimise the amount of data being written to the files. Examples of this are environmental data that might be useful for habitat studies or other more general science.

Therefore:

1. Allow the user to configure into the logger firmware a list of NMEA2000 PGNs (by decimal number) that should be preserved in the output (other than the core set that are already parsed and written to the output stream). This includes adding a command to CommandProcessor.cpp to set and query the list, and storage for these in NVM.
2. Add code to the JavaScript for the firmware website to allow for these PGNs to be specified.
3. Add a packet to the serialiser to encapsulate a raw NMEA2000 byte array with an elapsed time indicator; bump serialiser version.
4. Modify N2kLogger.cpp to match the PGNs against the configured list, and encapsulate the byte stream for these, for future parsing.
5. Modifiy packet reader Python to allow for the new version of the serialiser, and the new packet.
6. Add decode for the packet using the marulc library as for OpenVBI.
7. Allow for auxiliary output of the stored packets to ASCII output.
8. Bump version of the firmware.

[brian-r-calder]

A non-exhaustive list of interesting packets is:
• 129025 – Position, Rapid Update
• 129033 – Time & Date (may be moot because we capture SystemTime)
• 128259 – Speed Through Water
• 127250 – Heading
• 130306 – Wind Speed, Wind Direction