URL suffix problem

Hi @johno , great theme, I just love the design & simplicity of it.

But there's a small problem, is that when running at local, the url to a .md file (not in the `_post` folder) should not contain ".md" suffix, however, when it goes to github pages, urls only work with the ".md" suffix appended to it, so I have to remove ".md" to make it work locally, and remove ".md" to make it work online.

Is there any quick fix to this?

Thanks a lot!
Adam