Initial impl of capping MAU

return 404 if room not found

Improvements for Docker usage

rename replication_layer to federation_client

Rewrite cache list decorator

Per the Client-Server API[0] we should return
`M_NOT_FOUND` if the room isn't found instead
of generic SynapseError.

This ensures that /directory/list API returns
404 for room not found instead of 400.

[0]: https://matrix.org/docs/spec/client_server/unstable.html#get-matrix-client-r0-directory-list-room-roomid



Signed-off-by: Serban Constantin <serban.constantin@gmail.com>

Remove pdu_failures from transactions

I have HAD ENOUGH of trying to remember wtf a replication layer is in terms of
classes.

Make EventStore inherit from EventFederationStore

Add some documentation for using the dashboard

Only import secrets when available

The field is never read from, and all the opportunities given to populate it are not utilized. It should be very safe to remove this.

secrets got introduced in python 3.6 so this class is not available
in 3.5 and before.

This now checks for the current running version and only tries using
secrets if the version is 3.6 or above

Signed-Off-By: Matthias Kesler <krombel@krombel.de>