encapsulate: implement INVOKE-WITH-TEMPORARY-PAGE like -DRAWING-OPTIONS
encapsulate: implement INVOKE-WITH-TEMPORARY-PAGE like -DRAWING-OPTIONS

Like INVOKE-WITH-DRAWING-OPTIONS, INVOKE-WITH-TEMPORARY-PAGE should
pass the encapsulating stream to the continuation (not the
encapsulated stream). Otherwise code like

  (with-encapsulating-stream (stream)
    (formatting-table (stream)
      ...
      (encapsulating-stream-stream stream)
      ...))

would fail because the value of the innermost STREAM binding would not
necessarily be an encapsulating stream.

fixes #859

slyrus/mcclim,slyrus/mcclim