Fixed #7382 -- Added a reference to Pisa HTML2PDF in the PDF output docs....

    * PDFlib_ is another PDF-generation library that has Python bindings. To

      use it with Django, just use the same concepts explained in this article.

    * `Pisa HTML2PDF`_ is yet another PDF-generation library. Pisa ships with

      an example of how to integrate Pisa with Django.

    * HTMLdoc_ is a command-line script that can convert HTML to PDF. It

      doesn't have a Python interface, but you can escape out to the shell

      using ``system`` or ``popen`` and retrieve the output in Python.

    * `forge_fdf in Python`_ is a library that fills in PDF forms.

.. _PDFlib: http://www.pdflib.org/

.. _`Pisa HTML2PDF`: http://www.htmltopdf.org/

.. _HTMLdoc: http://www.htmldoc.org/

.. _forge_fdf in Python: http://www.accesspdf.com/article.php/20050421092951834