Co-Authored-By: erikjohnston <erikj@jki.re>

When we receive events over federation we will need to know the room
version to be able to correctly handle them, e.g. once we start changing
event formats. Currently, we attempt to handle events in unknown rooms.

* port hash_password

* changelog

add purge_history.sh and purge_remote_media.sh scripts

Signed-off-by: Ruben Barkow <github@r.z11.de>

So people can still collect consent the old way if they want to.

fixes #4056

* Add helpers for getting prev and auth events

This is in preparation for allowing the event format to change between
room versions.

Clean up event accesses and tests

This is in preparation to refactor FrozenEvent to support different
event formats for different room versions

Fix locked upsert on device_lists_remote_cache

Fix logic error that prevented guests from seeing the privacy policy

Fix None exception in state res v2

The indexes on device_lists_remote_extremeties can be unique, and they
therefore should, to ensure that the db remains consistent.

We can rely on the application-level per-user linearizer.

Fix build of Docker image with docker-compose

Add m.login.terms to the registration flow

Add STATE_V2_TEST room version