First steps towards RadSec support

[Alan DeKok]

  Now that version 2.1.7 has been released, the git repository has been
updated with the first step to RadSec support.

  For now, it only provides RADIUS transport over TCP, as per the
following document:

http://tools.ietf.org/html/draft-dekok-radext-tcp-transport-01

  Using "bare" TCP without TLS is't a good idea in most cases.  But it's
useful for testing, and can help with the transition to RadSec.

  Alan DeKok.