Feature/channel settings

[ryan-summers]

This PR adds in support for persistent channel configuration settings.

This PR fixes #11

I have also added a TXT file containing the EEPROM contents of one of the RF modules for future reference.

The present channel configuration may be persisted to channel EEPROM using the booster utility script: python booster.py <CH> --save.

The channel configuration is composed of:

• Boolean indicating whether or not channel is enabled by default
• Linear transforms for output/input/reflected power (not yet configurable)
• Channel bias voltage
• Reflected + Output interlock threshold

Power measurement calibration is deferred to #69

Testing:

1. An RF channel was installed in channel 0 and the existing EEPROM contents were dumped to the TXT file in this PR.
2. The channel was configured with thresholds of 10dBm and 20dBm, the bias voltage was tuned (1.14V, 50mA), and the channel was enabled
3. Channel settings were persisted to nvm using python booster.py 0 --save
4. Booster was reset over the USB terminal
5. Upon boot, it was confirmed that the channel remained enabled, the bias was set, and the thresholds were configured by observing the MQTT telemetry reports.

[jordens]

Don't change the boot-up configuration here. The enable-on-boot setting should be separate from the enable/disable commands and the latter should not touch that setting. The setting should be (separately) configurable (like the thresholds and transforms).

[jordens]

Ah. I think this is already implemented by the save_config semantics, right? Then scratch it.

[ryan-summers]

Correct - settings are only updated in NVM when explicitly requeested to save over the MQTT control interface.

Right now, the settings are loaded from NVM and propagated to the channel. Then, the settings mirror the current state of the channel so they can be persisted to nvm immediately upon receipt of the save command - they are not otherwise persisted.