Handle deleted reported accounts in report admin API

Closes #1046

See merge request pleroma/pleroma!1370

This is to avoid 500 error when the reported user no longer exists
in the database.

Move changelog entries

See merge request pleroma/pleroma!1368

OTP Release install docs: Remove --dry-run in cron certbot command

See merge request pleroma/pleroma!1366

Add PLEROMA_BUILD_ENV to override env for the version generator and use it in the CI for building docs

See merge request pleroma/pleroma!1360

Update changelog and admin API docs with tags, display_name, avatar additions

See merge request pleroma/pleroma!1367

[#1033] Fix database migrations

See merge request pleroma/pleroma!1350

Add hashtag filter to user statuses (GET /api/v1/accounts/:id/statuses)

Closes #974

See merge request pleroma/pleroma!1362

[#1026] Filter.AnonymizeFilename added ability to retain file extension with custom text

Closes #1026

See merge request pleroma/pleroma!1363

Fix not being able to pin unlisted posts

Closes #1038

See merge request pleroma/pleroma!1364

Closes #1038

Add PLEROMA_BUILD_ENV to override env for the version generator and use it in the CI for building docs

This is needed because if we run with MIX_ENV=dev we will get a "+dev"
suffix to the version in the docs, but if we run with MIX_ENV=prod the
docs build will fail because ex_doc is dev-only dependency.

Docker specific configuration information

See merge request pleroma/pleroma!1359

Revert "Build releases only on tags or develop" on develop

See merge request pleroma/pleroma!1357

This reverts commit 54d28737.

Build releases only on tags or develop

See merge request pleroma/pleroma!1355

Needed so we could push documentation updates to master without
triggering a rebuild

Add a warning about service files assuming installation paths

See merge request pleroma/pleroma!1353

Move all upload contents despite upload folder itself.

See merge request pleroma/pleroma!1352

Update migrating_from_source_otp_en.md

See merge request pleroma/pleroma!1351

Merge admin and mastodon user views for reports

See merge request pleroma/pleroma!1346

MRF: add mediaproxy warming policy

See merge request pleroma/pleroma!1342

Fixed links in documentation

See merge request pleroma/pleroma!1334

Update docs/installation/arch_linux_en.md, docs/installation/centos7_en.md, docs/installation/debian_based_en.md, docs/installation/debian_based_jp.md, docs/installation/gentoo_en.md files

1.0 Release

See merge request pleroma/pleroma!1348

Docs on OTP releases

See merge request pleroma/pleroma!1315