Merge branch 'matthew/gin_work_mem' into matthew/hit_the_gin

.gitignore

CHANGES.rst

README.rst

docs/admin_api/media_admin_api.md

docs/admin_api/purge_history_api.rst

docs/metrics-howto.rst

scripts/move_remote_media_to_new_store.py

synapse/__init__.py

synapse/api/errors.py

synapse/app/appservice.py

synapse/app/client_reader.py

synapse/app/federation_reader.py

synapse/app/federation_sender.py

synapse/app/frontend_proxy.py

synapse/app/homeserver.py

synapse/app/media_repository.py

synapse/app/pusher.py

synapse/app/synchrotron.py

synapse/app/synctl.py

synapse/app/user_dir.py