v0.0.53 - swh.indexer.rehash: Migrate to latest swh.model.hashutil.MultiHash - indexer: Add the origin intrinsic metadata indexer - indexer: Add OriginIndexer and OriginHeadIndexer. - indexer.storage: Add the origin intrinsic metadata storage database - indexer.storage: Autogenerate the Indexer Storage HTTP API. - setup: prepare for pypi upload - tests: Add a tox file - tests: migrate to pytest - tests: Add tests around celery stack - docs: Improve documentation and reuse README in generated documentation