Given you have an existing website, it might be easier for you to add Markdown support to your site through a static site generator or server-side conversion step.

Or you can even use a Markdown-to-HTML tool (I believe pandoc has this feature) to convert the pages yourself before posting. That's a bit more manual but wouldn't require changing your current structure.

Anyway, if you end up using boilerplate, let me know what you think!