Control Repeater Upgrades (Again)

After using the upgraded control repeater a few times, it became apparent that having a power switch would be really useful, especially when doing the short flights with the Mojo.

I added a switch next to the model select switch, so instead of opening the lid and unplugging the battery, I can just quickly switch it off.

In addition, I added a voltage monitor/alarm which is easily visible through the top of the case. This is a good way to ensure the battery that's powering the ground station has plenty of life left, without having to use the telemetry cable from the repeater receivers.