Adding content sensitivity toggle, spoilers for media

app/assets/javascripts/components/actions/compose.jsx

...ssets/javascripts/components/components/media_gallery.jsx

...assets/javascripts/components/components/video_player.jsx

...s/components/features/compose/components/compose_form.jsx

...ts/features/compose/containers/compose_form_container.jsx

...components/features/status/components/detailed_status.jsx

app/assets/javascripts/components/reducers/compose.jsx

app/assets/stylesheets/components.scss

package.json

yarn.lock