RaceChrono: validate talker id's and NMEA messages

[renatobo]

According to this post, RaceChrono only accepts GPRMC and GPGGA so they can be disabled

Alternatively, adopt the same binary packet format described in racechrono-ble-diy-device other info at https://github.com/timurrrr/arduino-RaceChrono

Additional info also at the Tutorial on DIY devices which explains $RC2 and $RC3 formats

[renatobo]

From tests with current version 7.0.10

GGA and RMC minimum mandatory

• GNGGA, GNRMC are supported (combined GPS, Glonass) -> best option, matching the option 'Main Talker ID = 0 System Dependent'
• GPGGA, GPRMC are supported (combined GPS, Glonass)
• GL<GGA,RMC> and GA<GGA,RMC> are not supported

GBS

• it seems ignored -> remove from default

GSV and GSA

• only GP* supported
• GNGSV not supported, differently from support for GN in GGA and RMC

This means

• Disable GBS
• Change polling GSA and GSV to use GP instead of GN Talker
• Enable the option "Restrict output to GP SVs only"

New configuration option "racechrono" now holds the true/false status of these optimizations

[renatobo]

Open a separate issue for binary protocol support