Add an expiration command, which sets the expiration date of a
principal. Based on a patch from Garrett Wollman.
+ Add a pwexpiration command, which sets the expiration date of the
+ password of a principal.
+
+ Add a check_expire command, which returns the expiration date of
+ either a principal or a password.
+
kadmin backend for an MIT Kerberos server now supports the create_opts
configuration parameter, which adds additional options that are passed
to kadmin addprinc when a principal is created. Based on a patch by