Backport of: !3503

Backport of: !3503

grep -rl '# Copyright © .* Pleroma' * | xargs sed -i 's;Copyright © .* Pleroma .*;Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>;'

Fix follower/blocks import when nicknames starts with @

Closes #1698

See merge request !2416

Automatic checks of authentication / instance publicity. Definition of missing OAuth scopes in AdminAPIController. Refactoring.

Done via the following command:
git diff fcd5dd25 --stat --name-only | xargs sed -i '/Pleroma Authors/c# Copyright © 2017-2020 Pleroma Authors <https:\/\/pleroma.social\/>'

Adds Event support in the same way Video objects are handled, with the
name of the object as message header.
Signed-off-by: Thomas Citharel <tcit@tcit.fr>

OAuthScopesPlug: disallowed nil token (unless with :fallback option). WIP: controller tests modification: OAuth scopes usage.

[#1234] Merge remote-tracking branch 'remotes/upstream/develop' into 1234-mastodon-2-4-3-oauth-scopes

# Conflicts:
#	CHANGELOG.md
#	lib/pleroma/web/mastodon_api/controllers/mastodon_api_controller.ex
#	lib/pleroma/web/router.ex

Closes #1138