[Users] check displayname with proxy-authorizationname

[Juha Heinanen]

Hakan YASTI writes:

 > I want to check the "AUTHORIZATION_USERNAME" at proxy-authorization with the "DISPLAY_NAME" of the user agent.( I want them to be same ). 
 > How can I do this ? 

check if there exists pseudo variables for both and use avpops to make
the comparison.  if not, make a feature request.

-- juha