Parts Headings

[alanlujan91]

I'm working on a latex template, where I am adding an appendix as a "part" of the document.

parts:
    appendix: appendix.md

This seems to work, but it always demotes the headers in the appendix; for example, it turns # Appendix to a subsection instead of a section in LaTeX.

I would like it to be able to follow the headings hierarchy, where # Appendix is another top level section of the paper.