[reSIProcate-users] RADIUS support in repro, documentation

[Daniel Pocock <daniel@xxxxxxxxxxxxx>]

RADIUS code has been in the stack for some time but never been available
for repro users.

There is now an EnableRADIUS option in repro and a wiki about it
including details for setting up FreeRADIUS server:

https://www.resiprocate.org/RADIUS