It would nice if there were a simple mechanism to write
documents to stdout instead of a file on the
--If the filename argument is None for writePDFfile or
writeEPSfile, write to sys.stdout.
--Have writePDFfile and writeEPSfile take a file
argument, which defaults to sys.stdout. This gives the
added flexibility of using any file handle.
--Create new methods, writePDFToStdout and