Add duration parameter to muting. (#13831)

app/controllers/api/v1/accounts_controller.rb

app/controllers/api/v1/mutes_controller.rb

app/javascript/mastodon/actions/accounts.js

app/javascript/mastodon/actions/mutes.js

app/javascript/mastodon/components/account.js

app/javascript/mastodon/features/ui/components/mute_modal.js

app/javascript/mastodon/locales/en.json

app/javascript/mastodon/locales/ja.json

app/javascript/mastodon/reducers/mutes.js

app/javascript/styles/mastodon-light/diff.scss

app/javascript/styles/mastodon/components.scss

app/models/concerns/account_interactions.rb

app/models/mute.rb

app/serializers/rest/muted_account_serializer.rb

app/services/mute_service.rb

app/workers/delete_mute_worker.rb

db/migrate/20200317021758_add_expires_at_to_mutes.rb

db/schema.rb