Using Atom as a Markdown editor

Hi everyone,

I’ve just started up Atom for the first time to trial it as a Markdown editor (I currently use TextMate). I’ve dragged my “nvAlt” Dropbox folder, which is full of .md files, to the editor, hoping that they’ll all appear in the Project pane on the left. Alas, every file type except for .md shows up there. How do I make the .md files show up and hide the .plist (from Ulysses ;-)) and Notes and Settings (from TextMate, I assume ;-)) files?

Thanks, Andrew