Docs Could Use Some SEO Improvements

I noticed that the docs site could use some SEO improvements. Some of the items are that there's currently two page titles on each page instead of one, all pages have the same meta description, most pages have an odd page title like page.home, and Google Analytics isn't hooked up.

The main cause of most the issues seems to be that [jekyll-multiple-languages-plugin](https://github.com/kurtsson/jekyll-multiple-languages-plugin/) and [jekyll-seo-tag](https://github.com/jekyll/jekyll-seo-tag) don't play nicely together. I'm working on a fix where only the jekyll-multiple-languages-plugin is used and then the theme handles outputting the page title and various meta tags.