* Add animate custom emoji param to embed pages

* Rename param, use it for avatars and gifs

* Fix issues pointed by codeclimate and breaking test

* Ignore brakeman warning

- Use statuses controller for embeds instead of stream entries controller
- Prefer /@:username/:id/embed URL for embeds
- Use /@:username as author_url in OEmbed
- Add follow link to embeds which opens web intent in new window
- Use redis cache in development
- Cache entire embed

* Simplify render in mailer views

* Simplify render in about/more view

* Simplify render in accounts follow views

* Simplify render in recovery code views

* Simplify render in stream entry embed

* Simplify render in stream entries status partial

* Simplify render in authorize follow new view

fix #361 with rich OEmbed display via iframe, fix #237 by hiding sensitive
content behind a spoiler on public pages