Minor release with minor improvements and bug fixes.
What's Changed
* fixed bug with is_transformer by seanmacavaney in https://github.com/terrier-org/pyterrier/pull/274
* addresses [275 issue k in kmaxavg](https://github.com/terrier-org/pyterrier/issue/275), improved testing by cmacdonald in https://github.com/terrier-org/pyterrier/pull/276
* defer loading ir_datasets by seanmacavaney in https://github.com/terrier-org/pyterrier/pull/280
* Set meta and meta_lengths in constructor by MWschutte in https://github.com/terrier-org/pyterrier/pull/282
* Anserini fixes by cmacdonald in https://github.com/terrier-org/pyterrier/pull/279, reported by Azouu
* prevent use of nptyping v2 by cmacdonald in https://github.com/terrier-org/pyterrier/pull/291, reported by tabonnet
* SourceTransformer pass through extra columns, addresses 287 by cmacdonald in https://github.com/terrier-org/pyterrier/pull/288, reported by Xiao0728
* more transformers with repr by cmacdonald in https://github.com/terrier-org/pyterrier/pull/289
New Contributors
* MWschutte made their first contribution in https://github.com/terrier-org/pyterrier/pull/282
**Full Changelog**: https://github.com/terrier-org/pyterrier/compare/0.8.0...0.8.1