First steps to adding a blog.

Post template, blog index page.
Portions inspired by jekyll-bootstrap, though I don't expect much of that to stay in the final version.
Merge branch 'staging' into blog
Merge branch 'staging' into blog
Add date to YAML headers with timestamp
Formatting changes for future.

Notable change is now we have a 'page' layout that uses the page title to generate the <h1> for the page as well as the the page title itself.
Merge commit '9727d46cff8cca5397553ca721d6e2a7ab14dcb3' into knitr_test

Adds in the formatting features for blogs, minus test posts.
Conflicts:
	css/default.css
Add course page layout.