* Draupnir for all Role

* Draupnir for all Documentation

* Pin D4A to Develop until D4A patches are in a release.

* Update D4A Docs to mention pros and cons of D4A mode compared to normal

* Change Documentation to mention a fixed simpler provisioning flow.

Use of /plain allows us to bypass the bugs encountered during the development of this role with clients attempting to escape our wildcards causing the grief that led to using curl.

This reworded commit does still explain you can automatically inject stuff into the room if you wanted to.

* Emphasise the State of D4A mode

* Link to Draupnir-for-all docs and tweak the docs some

* Link to Draupnir-for-all from Draupnir documentation page

* Announce Draupnir-for-all

---------

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

This paves the way for installing other roles into `roles/galaxy` using `ansible-galaxy`,
similar to how it's done in:

- https://github.com/spantaleev/gitea-docker-ansible-deploy
- https://github.com/spantaleev/nextcloud-docker-ansible-deploy

In the near future, we'll be removing a lot of the shared role code from here
and using upstream roles for it. Some of the core `matrix-*` roles have
already been extracted out into other reusable roles:

- https://github.com/devture/com.devture.ansible.role.postgres
- https://github.com/devture/com.devture.ansible.role.systemd_docker_base
- https://github.com/devture/com.devture.ansible.role.timesync
- https://github.com/devture/com.devture.ansible.role.vars_preserver
- https://github.com/devture/com.devture.ansible.role.playbook_runtime_messages
- https://github.com/devture/com.devture.ansible.role.playbook_help

We just need to migrate to those.

* Add matrix-registration-bot

This adds an install and uninstall task plus helpers. The bot is disabled by default.
This commit does not include documentation, yet. In short, the bot can be enabled by adding
matrix_bot_matrix_registration_bot_enabled: true
matrix_bot_matrix_registration_bot_matrix_user_password: "verysecret"
matrix_bot_matrix_registration_bot_matrix_admin_token: "supersecret"
to the host_vars

* Change bot username to bot.matrix-registration-bot following convention

* Address smaller remarks, fix local docker build

* Switch to an env file

* Add environment variables extension for additional config

* Add documentation for the matrix-registration-bot

* Add screenshot on how to obtain admin access token

* Use bot as admin to only have one access token (bot and admin api)

* Use cleaner setting of matrix_synapse_registration_requires_token

* Use config file for cleaner more secure usage

* Delete unneeded env

* Rename vars to make usage clear

* Fix typos/wording and add notice about logging out

* Convert configuration to use |to_json

* Reorder role includes

Nothing should be after `matrix-common-after`.

`matrix-bot-matrix-registration-bot` can probably be anywhere, but it makes sense to put it next to the other `matrix-bot-*` roles.

* Minor group_vars/matrix_servers touchups

Co-authored-by: Slavi Pantaleev <slavi@devture.com>