Merge branch 'require-signature' into 'develop'

Add an option to require fetches to be signed

Closes #1444

See merge request pleroma/pleroma!2071

diff --cc CHANGELOG.md
index ce0f584cba9342aa223d2ae7aaf0a8c2e1d6965c,93c7485aa11d1d4fb221cd641c38bac8c281a0d3..4127e21f753fc596780072395723a8957114380d
--- 1/CHANGELOG.md
--- 2/CHANGELOG.md
+++ b/CHANGELOG.md
@@@ -70,10 -51,9 +70,11 @@@ The format is based on [Keep a Changelo
  - Support for `X-Forwarded-For` and similar HTTP headers which used by reverse proxies to pass a real user IP address to the backend. Must not be enabled unless your instance is behind at least one reverse proxy (such as Nginx, Apache HTTPD or Varnish Cache).
  - MRF: New module which handles incoming posts based on their age. By default, all incoming posts that are older than 2 days will be unlisted and not shown to their followers.
  - User notification settings: Add `privacy_option` option.
 +- Support for custom Elixir modules (such as MRF policies)
  - User settings: Add _This account is a_ option.
 +- A new users admin digest email
  - OAuth: admin scopes support (relevant setting: `[:auth, :enforce_oauth_admin_scope_usage]`).
+ - Add an option `authorized_fetch_mode` to require HTTP signatures for AP fetches.
  <details>
    <summary>API Changes</summary>
  

diff --cc config/config.exs
Simple merge

diff --cc docs/configuration/cheatsheet.md
Simple merge