pull up r18923 from trunk

pull up r18923 from trunk

 r18923@cathode-dark-space:  lxs | 2006-12-05 18:21:56 -0500
 ticket: new
 owner: tlyu
 target_version: 1.6
 subject: krb5_cc_remove should work for the CCAPI
 tags: pullup

 Implemented a working krb5_cc_remove for the CCAPI cache type.  Added a
 private support function krb5_creds_compare() which checks if two krb5_creds
 are identical.  This function should be needed by implementations of
 krb5_cc_remove for other ccache types.

ticket: 5003
version_fixed: 1.6

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-6@18928 dc483132-0cff-0310-8789-dd5450dbe970