Feature request: Allow RxMode to be assigned to programmable buttons

[mightyohm]

I find myself wanting to change RxMode frequently. For example, when I am generally monitoring, I like to use MAIN TX DUAL RX so I can listen to a local repeater as well as my ClearNode. During nets I change to MAIN ONLY so that my reception of the net won't be interrupted by traffic on the second receiver.

Can we get the RxMode setting added to the list of items that can be assigned to a programmable button? This would make it trivial to switch RxModes and would be super handy,

Cheers,
Jeff W6OHM