Moving mrf settings from instance to separate mrf group

Closes #1631

See merge request pleroma/pleroma!2320

[#1798] fixed migration the settings to DB

See merge request pleroma/pleroma!2655

Fix 1586 provide index md

See merge request pleroma/pleroma!2669

ActivityPubController: Update upload_media @doc

See merge request pleroma/pleroma!2673

Small cherry-pick from pleroma/pleroma!1810

Add missing default config value for :instance, instance_thumbnail

See merge request pleroma/pleroma!2672

Follows up on b7fc61e1

Add warning against parsing/reusing MastoFE settings blob

See merge request pleroma/pleroma!2671

Add `pleroma.is_muted` property to notifications

Closes #1812

See merge request pleroma/pleroma!2670

account visibility in masto api

Closes #1739

See merge request !2488

Add include for the "Further reading" section

See merge request pleroma/pleroma!2667

Proper error codes for error in adminFE

Closes #1825

See merge request !2665

Translations update from Weblate

See merge request !2661

* I renamed the introduction.md to index.md
* I moved over the FE parts to an index file in the FE repo (will do an MR in the FE repo to actually add it)
* While I was at it, I also fixed some broken links

Currently translated at 0.9% (1 of 106 strings)

Translation: Pleroma/Pleroma backend
Translate-URL: https://translate.pleroma.social/projects/pleroma/pleroma/it/

Resolve "/api/v1/accounts/:id/statuses?only_media=true returns media that is not owned"

Closes #1865

See merge request pleroma/pleroma!2650

HellthreadPolicy: Restrict to Notes and Articles.

Closes #1883

See merge request !2666

* I added an include and use this include for the installation guides that already had this section
* I added the "Further reading" section as well as te "Questions" section to the English guides that didn't have it yet
* I added a first point "How Federation Works/Why is my Federated Timeline empty?" to link to lains blogpost about this because we still get this question a lot in the #pleroma support channel
* I reordered the list a bit

Emoji and packs pagination

Closes #1854

See merge request !2658

mix.exs: version git-less (part 2, MacOS-compat)

See merge request !2420

Support 'bot' field in account update_credentials

Closes #1600 and #1467

See merge request !2662

cheatsheet.md: no_attachment_links → attachment_links

See merge request !2664

Stop filling conversation field on incoming objects (legacy, unused)

See merge request !2663

# Conflicts:
#   CHANGELOG.md