twisted.cred.portal.IRealm docstring for parameters

[thomasvs]

this docstring is missing argument descriptions.
attaching patch.

[exarkun]

There should certainly be a docstring for this.  The docstring in this patch
isn't totally accurate though.  cred is useful for more than just pb.  In the
case of a PB realm, the types described in the patch are correct, but in the
case of a realm for any other protocol, they are not.

I'm not sure what a better doc string would look like, but it should cover these
points:

  1) avatarId is generally a string, but not necessarily one.  The realm,
credentials checkers, and client code need to come to an agreement on this
themselves.

  2) The realm is essentially an application-specific object.  It is often None
and ignored, but when it is necessary for the realm to initiate communications
with the client, rather than (or in addition to) the reverse, it is useful to
create a client object of some sort and pass it as the parameter for the mind.

[teratorn]

Any progress on this?

[radix]

exarkun meant to say "mind", not "realm" at the beginning of his point 2.

[radix]

closing, there are quite sufficient argument descriptions in the docstring 
as it stands. maybe someone added them and forgot to close this