Merge remote-tracking branch 'origin/release-v0.12.0'

AUTHORS.rst

CHANGES.rst

README.rst

docs/postgres.rst

jenkins.sh

scripts-dev/definitions.py

scripts/gen_password

synapse/__init__.py

synapse/api/auth.py

synapse/api/errors.py

synapse/api/filtering.py

synapse/app/homeserver.py

synapse/config/server.py

synapse/crypto/keyring.py

synapse/events/utils.py

synapse/federation/transport/server.py

synapse/handlers/_base.py

synapse/handlers/account_data.py

synapse/handlers/admin.py

synapse/handlers/events.py