Octicons

- New "changes requested" icon https://github.com/primer/octicons/pull/267
- Contrib Doc Updates https://github.com/primer/octicons/pull/256
- Updating licenses to 2019 https://github.com/primer/octicons/pull/272

- Add `fold-up` and `fold-down` icons, courtesy of pmarsceill

- Add `eye-closed` icon, courtesy of colinkeany

- Patch release for failed 8.1.1 release

- Fix for `list-ordered` icon https://github.com/primer/octicons/pull/252
- In React Octicons, we set aria-hidden to false if there's an aria-label provided

- Add the `arrow-both` icon courtesy of venetucci
- TypeScript types are now available thanks to j-f1!
- Fix CI builds for outside contributors (as long as they aren't changing octicons)
- Fix typo in README
- Update README with `githubprimer/octicons-react scope`
- Publish release candidates from any branch beginning with `release`