Use jekyll-seo-tag plugin

[petk]

There is a jekyll-seo-tag plugin used on GitHub pages that can automatically output SEO metadata and add Open Graph with Twitter cards tags etc.

I've added additionally this value tagline: Reference for PHP best practices which is appended to title on the index page.

https://pages.github.com/versions/

[Xymph]

I know nothing about this, so punting to @codeguy .