(direct-print-region-function): Try to ensure that

(direct-print-region-function): Try to ensure that
printer-name is expanded to a file name on a local drive;
sometimes printing a file loaded from a network volume fails.
(direct-print-region-function): Add a function to
write-region-annotate-functions to append a formfeed character to
the region being printed, if the region doesn't end with a
formfeed already.  This avoids creating a second print job
containing a blank page when print spooling is enabled on Windows.