[OpenAFS] Added token passing to SSH protocol 2

[Rainer Laatsch]

Patches to enhance openssh-4.7p1 for AFS token and KRB5 ticket passing
in protocol 2 can be found in
 /afs/rrz.uni-koeln.de/admin/public/openssh-4.7p1-PatchDir/
These also allow AFS token passing in protocol 1 for backward compatibily.

Users can do single sign on with an ssh key in protected AFS space.
No rearrangement to the location of the 'authorized_keys' file is needed.

Best regards,
Rainer Laatsch