Merge branch 'develop' into auth

demo/start.sh

setup.cfg

setup.py

synapse/federation/federation_client.py

synapse/federation/federation_server.py

synapse/federation/transport/client.py

synapse/federation/transport/server.py

synapse/handlers/federation.py

synapse/handlers/message.py

synapse/handlers/presence.py

synapse/handlers/sync.py

synapse/http/matrixfederationclient.py

synapse/metrics/__init__.py

synapse/python_dependencies.py

synapse/rest/client/v2_alpha/keys.py

synapse/state.py

synapse/storage/_base.py

synapse/storage/directory.py

synapse/storage/event_federation.py

synapse/storage/keys.py