Write some documentation on performance characteristics for single radio, multiple VAP devices

[jheretic]

Although we've often used devices such as picostations for both nodes and access points for small-scale and demo networks, using those devices for both functions simultaneously in a large or busy network can have major performance impacts. We should write up some documentation on general performance guidelines for the use of single-radio devices.

[andygunn]

#319 Should address some of these questions