Added the following enabled-by-default plugins (+ a default theme):
- Jekyll Optional Front Matter - Don't require optional front matter to process a page as a page
- Jekyll README Index - If a repo has a readme, but not an index, use the readme as the index
- Jekyll Default Layout - Set a default per-page layout if no layout is specified and a logical one exists for the site
- Jekyll Titles from Headings - If there is no YAML title, use the first hading as the page's title