Needs to be backported to stable.

Related: pleroma-support#29

Better advice for vacuuming after restoring.

See merge request pleroma/pleroma!2233

mix.exs: bump version to development one

See merge request !2279

Sync develop with stable

Closes #1262, #1267, #1293, #1303, #1287, #1291, #1382, #1438, #1129, #1109, and #1606

See merge request !2278

Release/2.0.0

See merge request !2273

moderation log: fix improperly migrated data

See merge request !2277

Some of the actions used to have a user map as a subject, which was then
changed to an array of user maps. However instead of migrating old data
there was just a hack to transform it every time, moreover this hack
didn't include all possible actions, which resulted in crashes. This
commit fixes the crashes by introducing a proper database migration for old data.

Closes #1606

Wait in mix task while pleroma is rebooted

See merge request !2225

Remove EmojiPacks from AdminFE build

See merge request !2275

Revert "Merge branch 'update/admin-fe-without-emojipack' into 'develop'"

See merge request !2276

This reverts merge request !2274

Once more, with feeling

Remove emoji support from AdminFE

See merge request !2274

MastodonController: Return 404 errors correctly.

See merge request !2270

Generate instance stats on startup

Closes #1598

See merge request !2271

Exclude reblogs from `GET /api/pleroma/admin/statuses` by default

Closes #1596

See merge request pleroma/pleroma!2267

Do not fail when user has no email

See merge request !2249

Update Copyrights

See merge request !2269

Prepared statements settings

See merge request pleroma/pleroma!2238

fix for :fetch_initial_posts

See merge request !2266

A warning was added, but their were some newlines and whitespaces missing which broke the rendering of the setting. I've added them now

ActivityPub actions & side-effects in transaction

Closes #1482

See merge request pleroma/pleroma!2089

Bump copyright

See merge request pleroma/pleroma!2265

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\/>'