Also, lock babel deps to 7.0.0-beta.2 so that we are on the safe side.

* Add dispose methods in our documentation

* Update buttons.md

The old ones are still being redirected.

1. Add `alt=""` for the Bootstrap logo
2. Replace the HTML entities with the unicode symbols
3. Refactor the badges to something that makes more sense to me
4. Change `Selenium Test Status` alt attribute to `Sauce Labs Test Status`
5. Use shields.io for the peerDependencies badge too
6. Add CSS and JS gzip size badges, shoutout to @ngryman
7. Add a few more trailing slashes to URLs
8. Change link to tooling setup to the website one

This is required for Sass v3.5+ compatibility.
See https://github.com/sass/sass/blob/stable/doc-src/SASS_CHANGELOG.md#backwards-incompatibilities----must-read and https://github.com/sass/sass/issues/2383

It was mistakenly the same as lightning.svg.

Using `rgba($white,1)` results in `white` instead of the hex.

We actually want to generate a sourcemap for docs.min.css.