Use the list of encryption types passed as part of the KDC request to

Use the list of encryption types passed as part of the KDC request to
determine which encryption to use for encrypting the ticket.  The
encryption must be one that is supported by the KDC, as well as being
one which is marked as being supported by the server of the ticket.
In a AS request, also use this encryption for encrypting the KDC
response.  In a TGS request, use the encryption type of the TGT
authenticator to determine how to encrypt the KDC response.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@4712 dc483132-0cff-0310-8789-dd5450dbe970