Nu Shell Updates - Week #52

# This week in Nu #52 One year of TwiN! - samhedin changed per-directory environments to [run exit scripts in the original directory](https://github.com/nushell/nushell/pull/2352) - JosephTLyons updated [`histogram` occurrences examples](https://github.com/nushell/nushell/pull/2354), added a [test for `count`](https://github.com/nushell/nushell/pull/2358), fixed [column count breaking on empty tables](https://github.com/nushell/nushell/pull/2374) - mattclarke renamed [time units (eg `1s` is now `1sec`)](https://github.com/nushell/nushell/pull/2356) - jonathandturner changed `to json` to [preserve metadata in output](https://github.com/nushell/nushell/pull/2359), moved [nu-cli data functionality into its own crate, nu-data](https://github.com/nushell/nushell/pull/2369), added [testing wasm to CI](https://github.com/nushell/nushell/pull/2372) - lucasmmg changed [`sort-by` to fail gracefully when types are mismatched](https://github.com/nushell/nushell/pull/2360), and [further improved the error](https://github.com/nushell/nushell/pull/2366) - rrichardson added [new case conversions to `str`](https://github.com/nushell/nushell/pull/2363) - andrasio cleaned up [config settings logic](https://github.com/nushell/nushell/pull/2364) - fdncred added support for [more Nu table themes](https://github.com/nushell/nushell/pull/2365), and more [table theming](https://github.com/nushell/nushell/pull/2378) - bailey-layzer added [type inference for alias definitions](https://github.com/nushell/nushell/pull/2377) - LhKipp added a [`sleep` command](https://github.com/nushell/nushell/pull/2381), fixed [time units in the book](https://github.com/nushell/book/pull/125) - jzaefferer improved [tracking errors on the demo site](https://github.com/nushell/demo/pull/59), and updated the demo to the latest Nu - oylenshpeegal fixed a [typo in the contributor book](https://github.com/nushell/contributor-book/pull/28)

This week's Nu Shell update includes changes such as per-directory environment fixes, histogram example updates, time unit renaming, JSON metadata preservation, improved sorting, new case conversions for strings, config setting cleanup, enhanced table themes, alias type inference, a 'sleep' command, and improvements to the demo site and documentation.