SYSTEM MODES for mesh devices don't mention mesh radio behaviors

[dmiddlecamp]

I was very surprised to learn that setting my device into manual mode impacted the mesh radio on my gateway differently than it did on my xenon. (since the xenon seemed to turn it on for Particle.connect... but the boron didn't!)

can we fully document this behavior and provide examples? I can't tell if the device firmware is broken, or how these things are meant to work.