Migrate page layouts to Jekyll includes

[1ec5]

GitHub Pages has Jekyll built in, which allows us to avoid duplicating the raw HTML for page navigation etc. on every page. We should migrate the page layouts to Jekyll includes and move each page into a “post”. This will make it much easier to make sitewide changes, such as the recent name change or the social media icons being rejiggered in #92 #93 #94.

[1ec5]

GitHub has a guide to adopting Jekyll. I think we can migrate the site navigation over to Jekyll as a first step, since that’s the main pain point, while keeping everything else as pages. Later, we can migrate some of the pages to posts and turn our layouts and styling into a theme (or adapt a ready-made theme such as Dogwood).