Merge remote-tracking branch 'upstream/master' into feat-dockerfile

synapse/federation/federation_base.py

synapse/federation/federation_client.py

synapse/federation/federation_server.py

synapse/federation/send_queue.py

synapse/federation/transaction_queue.py

synapse/federation/transport/server.py

synapse/handlers/appservice.py

synapse/handlers/federation.py

synapse/handlers/message.py

synapse/handlers/register.py

synapse/handlers/room_list.py

synapse/handlers/room_member.py

synapse/handlers/sync.py

synapse/http/endpoint.py

synapse/http/server.py

synapse/http/site.py

synapse/metrics/__init__.py

synapse/metrics/metric.py

synapse/notifier.py

synapse/python_dependencies.py