The readme was getting pretty unmanageable and hard to grok. This is an attempt to simplify things by moving installation instructions from the README to a separate file. I've tried to resist the temptation to fix too much stuff while I'm here - it mostly just copies-and-pastes from one doc to the other, and changes from rst to md syntax.

Co-Authored-By: anoadragon453 <1342360+anoadragon453@users.noreply.github.com>

Co-Authored-By: anoadragon453 <1342360+anoadragon453@users.noreply.github.com>

* update debian installation instructions

* docs PR is docs

* remove dh_params and set better cipher string

* Update README to not lie about required restart

Signed-off-by: Aaron Raimist <aaron@raim.ist>

* Add changelog

Signed-off-by: Aaron Raimist <aaron@raim.ist>

Signed-off-by: Aaron Raimist <aaron@raim.ist>

Make the dependencies more like a standard Python project and hook up the optional dependencies to setuptools (#4298)

This is based on the work done by @krombel in #2601.

https://github.com/vector-im/vector-web/issues/1977 --> https://github.com/vector-im/riot-web/issues/1977
And mention of Vector as a client replaced with Riot.

Signed-off-by: Ashe Connor <ashe@kivikakk.ee>

Signed-off-by: Slavi Pantaleev <slavi@devture.com>

Signed-off-by: Aaron Raimist <aaron@raim.ist>

... to stop things which try to import `types` getting `synapse.types` instead

Link to contrib/docker

wrap at 80ish

This addresses #3224

Especially useful for the debian repo, as this makes it easier to get the key in a secure way