Radio Control Support

[comeadhra]

Adding support for Radio Control

[psigen]

Looks pretty good, I need to do a few minor cleanups and then it should be good to merge 👍

[psigen]

Why do we disable twice here? We could just wait 1s after the first disable, right?

Or is this a typo?

[comeadhra]

It's a typo. I removed it before, but it must have got back in somehow.

[jjblum]

I am going to attempt to use an SBUS based RC receiver. This digital format may solve the vague PWM range issues and provide up to 16 channels on a single RX wire. The receiver and transmitter are a bit more expensive, but I think the system should be improved and will allow control of multiple boats (though only one at a time) from a single transmitter. If it does work out, we'll need to decide if we want to merge this PWM based code or the SBUS version.

There may be a way of creating a more general class so that both can be supported. I will look into it.