File conversion support for markdown - odt

[juliusknorr]

As shown today markdown support is coming to Collabora Online, so we should implement that with our conversion API

[juliusknorr]

** docs/conversion_api.rst **
Will be available at https://sdk.collaboraonline.com/docs/conversion_api.html for the 25.04.8.1

``template`` – Template Option
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   This option allows specifying a template document that provides styles for the import result,
   so those template styles are used instead of the default styles.

Markdown Import Option
++++++++++++++++++++++

   The markdown import uses styles in the import result, so you can modify the formatting by providing a custom template.
   Example:

   curl -k -F "[data=@test.odt](mailto:data=@test.odt)" -F "template=@shaded.docx" -F "format=pdf" https://localhost:9980/cool/convert-to > out.pdf

   A custom template can be authored by creating an empty document and specifying no content,
   just styles, e.g. the ``Heading 1`` paragraph style and so on.

``compare`` – Compare Option
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   This option allows specifying an old / basline document that will be compared with the current
   document, automatically inserting the differences as tracked changes into the document.

Writer Import Option
++++++++++++++++++++

Writer documents (DOCX, ODT, etc.) implement this option. Example:

   curl -k -F "data=@new.docx" -F "compare=@old.docx" -F "format=pdf" -o out.pdf https://localhost:9980/cool/convert-to