[Devel] loop detection fix

[Juha Heinanen]

Daniel-Constantin Mierla writes:

 > The issue is with hash value. Somehow should ensure unique values, but 
 > most algorithms dont. They recommend in draft to use md5 which has low 
 > probability of collision.

i guess that md5 is the best there is.

 > Also, Route set has to be taken in consideration. Not usre if R-URI and 
 > Routes have to be canonized -- r-uri to username/host/port/proto and 
 > route to host/port/proto.

route set would need to be included only if proxy configuration allows
pre-loaded route set that includes more routes than one for the proxy
itself.  this could be a module parameter.

i don't think that any canonization would be needed, since if host name
gets changed to ip/port, then loop would be detected next time when that
same ip/port shows up in r-uri.

-- juha