* Implement new procedure STANDARD-UNPARSER-METHOD. This has a

* Implement new procedure STANDARD-UNPARSER-METHOD.  This has a
  less-idiosyncratic interface than UNPARSER/STANDARD-METHOD.  Uses of
  the latter should be replaced with the former.

* Implement new procedure WITH-CURRENT-UNPARSER-STATE which calls its
  second argument with the port from its first.  The other components
  of the state are fluid-bound so that they become the defaults for
  calls to WRITE and DISPLAY.

* GUARANTEE-UNPARSER-STATE and GUARANTEE-UNPARSER-TABLE now take an
  addition argument, the name of the procedure testing its argument.