add GitHub Flavored Markdown to README
add GitHub Flavored Markdown to README

* This makes the example code easier to read,
  especially when perusing the docs on github
labhackercd/dashing-rails,gottfrois/dashing-rails,mallikarjunayaddala/dashing-rails,gnagel/dashing-rails,DiningCity/dashing-rails,labhackercd/dashing-rails,gnagel/dashing-rails,mallikarjunayaddala/dashing-rails,DiningCity/dashing-rails,stewartmckee/dashing-rails,DiningCity/dashing-rails,stewartmckee/dashing-rails,mallikarjunayaddala/dashing-rails,gottfrois/dashing-rails,stewartmckee/dashing-rails,gottfrois/dashing-rails,labhackercd/dashing-rails,gnagel/dashing-rails