Merge pull request #99 from matrix-org/schema_versioning

synapse/app/homeserver.py

synapse/storage/__init__.py

synapse/storage/schema/delta/11/v11.sql

synapse/storage/schema/delta/12/v12.sql

synapse/storage/schema/delta/13/v13.sql

synapse/storage/schema/delta/14/upgrade_appservice_db.py

synapse/storage/schema/delta/v2.sql

synapse/storage/schema/delta/v3.sql

synapse/storage/schema/delta/v4.sql

synapse/storage/schema/delta/v5.sql

synapse/storage/schema/delta/v6.sql

synapse/storage/schema/delta/v8.sql

synapse/storage/schema/delta/v9.sql

synapse/storage/schema/filtering.sql

synapse/storage/schema/full_schemas/11/event_edges.sql

synapse/storage/schema/full_schemas/11/event_signatures.sql

synapse/storage/schema/full_schemas/11/im.sql

synapse/storage/schema/full_schemas/11/keys.sql

synapse/storage/schema/full_schemas/11/media_repository.sql

synapse/storage/schema/full_schemas/11/presence.sql