[Language Reference](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-10.0/file-scoped-namespaces) Updates all the files, one less level of indentation. Some small changes were made to API surfaces, renaming `PKM pkm` -> `PKM pk`, and `LegalityAnalysis.pkm` -> `LegalityAnalysis.Entity`
* Rewrite tests with XUnit and .Net Core * Add better "because" message * Skipping test that was not ready & convert the fact to a theory * Tweak casing * Convert select date tests to theories * Make the GetStringList load lock safer
