We only store signatures for relayables if the author is external, but
if the author becomes external through a migration, the signature is
missing. Lets just use the old persons private key to still be able to
generate a signature for the export.

closes #8310

If the migration contains a new remote_photo_path migrate all photos of
the old person to this path. If the person was local before, cleanup old
uploaded files of the photos.

closes #8314

closes #8317

closes #8316

closes #8313

closes #8304

closes #8037

fixes #8139
closes #8242

Also backported from #7660

I think this is a leftover from a long time ago and I can't find
anything that still uses that

closes #8280

Person.find_or_fetch_by_identifier raises an exception if person is not found localy and not fetchable. It never returns nil. These code changes take care about this behaviour and changes specs and code to behave equally.

Also related to #8253

Using galleries default border radius Small indicator images in image gallery are round ones, this doesn't correspond with preview shown in stream. It also doesn't look good on real-world images. (may look OK for User profile images)

closes #8275

This reverts b3ca504c. We don't quite know why that was added, but we assume it's because of format strings. Some pre-2011 users exist that still have dots or dashes in their username, and those accounts are somewhat broken now.

closes #8266

The chat is already removed for 0.8, so there is no need to still export
this data since it can't be imported anyway.

Related to #8069

closes #8265

closes #8263

closes #8262

closes #8159

closes #8244

- Fix rubocop styles
- Improve specs coverage

closes #8251
closes #8158

closes #8241
closes #7992

closes #8214
closes #8048

Co-authored-by: Thorsten Claus <thorstenclaus@web.de>

closes #8213
closes #7696

Co-authored-by: Hank Grabowski <hankgrabowski@gmail.com>
Co-authored-by: Thorsten Claus <thorstenclaus@web.de>

closes #8227

Updated settings for MapTiles as recommended by leaflet.js
Updating current licence text

Closes #8209
closes #8215

closes #8207

closes #8193

closes #8174

YAML is just too easy to get wrong

closes #8132