Grain 0.2.18

• New features:
  • Added PyGrain telemetry metrics (bytes read, read latency, and prefetch depth) for OSS via Prometheus.
  • Added support for non-sequence meta-features in PyGrain packing transformations.
• Bug fixes:
  • InterleaveDatasetIterator now overrides start_prefetch() such that it indeed starts prefetching (it did not do anything before).