Stupidb

Performance
* Reduce the amount of new object creation if rows' ids are the same as requested ([`3afad30`](https://github.com/cpcloud/stupidb/commit/3afad30cba4a49ed3b26e95347ce0e49a851a956))

Breaking
* Various objects that were previously accidentally public like Relation are no longer public ([`ea73691`](https://github.com/cpcloud/stupidb/commit/ea7369170af0a688d7370a69fa1f3dccd5a895d8))

Documentation
* Proper license ([`437abc0`](https://github.com/cpcloud/stupidb/commit/437abc0efea08da3effdec04a7c9c8fe4d79fa61))
* Move to markdown for top-level docs ([`1f46655`](https://github.com/cpcloud/stupidb/commit/1f466555aeb945b2be6ede3a0ab75fb09053ed38))
* Update requirements.txt ([`2c07ae8`](https://github.com/cpcloud/stupidb/commit/2c07ae8d39d647a6b4dc825074c491e7406868ff))

Feature
* Add limit operator ([`e0e6146`](https://github.com/cpcloud/stupidb/commit/e0e6146bb2efe65fafa417089aa69d421930c00f))

Feature
* **nixpkgs:** Bump ([`b7c5581`](https://github.com/cpcloud/stupidb/commit/b7c558138b10178d871d388a5c5d6e3e8ca9db35))

Documentation
* Add more docs ([`c2625dc`](https://github.com/cpcloud/stupidb/commit/c2625dc4f3c33f0eb597ff400b0b9527dfce3b67))
* **pyproject:** Add 3.8 and 3.9 metadata ([`da8365c`](https://github.com/cpcloud/stupidb/commit/da8365c983635cf00b78433730ea3845e4d1897f))

Feature
* **nixpkgs:** Bump ([`ef95630`](https://github.com/cpcloud/stupidb/commit/ef95630e49d66b997805b406913432e32676c1d7))

Feature
* **nixpkgs:** Bump ([`94509cb`](https://github.com/cpcloud/stupidb/commit/94509cbce4774c4b17dc42536064a081caeaa8de))