* pam_krb5afs.c(pam_sm_setcred): rename to setcred_int() so that we can do
    	proper debug logging and control whether or not we change the ownership
    	of newly-created files.  Remove existing v5 or v4 files which were
    	already created by the module before creating new ones.
    * pam_krb5afs.c(pam_sm_authenticate): use setcred_int() to avoid tripping over
    	permissions problems.
    * pam_krb5afs.c(pam_prompt_for): rework to provide varargs functionality for
    	the prompt text.
    * pam_krb5afs.c(pam_sm_authenticate,pam_prompter): use it.
    * pam_krb5afs.c(pam_sm_chauthtok): heed use_first_pass when reading the current
    	password, use_authtok when reading the new password.  Don't leak the
    	unparsed name.  Notify the user of why a change was rejected if that's
    	what happened.
    * pam_krb5afs.c(parse_user_name): add, to override the local realm name with
    	the configured realm before passing the user name to krb5_parse_name().
    	Replaces krb5_parse_name() wherever user names are passed in.