FluentValidation 9.0.0-preview4

FluentValidation 9 is a major release. Please read the upgrade notes at https://docs.fluentvalidation.net/en/latest/upgrading-to-9.html Changes in 9.0.0: * Removed support for netstandard1.1 and netstandard1.6 * Removed support for end-of-life .NET Core versions (2.2 and 3.0). LTS versions are supported (2.1 and 3.1) * Default email validation mode now uses the same logic as ASP.NET Core. Previous regex behaviour is opt-in. * TestHelper advanced mode now has more features (see https://docs.fluentvalidation.net/en/latest/testing.html#advanced-test-extensions) * Equal/NotEqual now perform ordinal comparison when used with string properties * Severity can now be set dynamically with a callback * Removed WithLocalizedMessage (WithMessage that takes a callback is the replacement) * Removed ResourceName from ValidationFailure * Removed ResourceName and ResourceType from IStringSource. * Removed SetCollectionValidator which was deprecated in 8.0 * Additional overload of OnAnyFailure that can receive a collection of validation failures * Remove DisplayAttribute integration and reference to DataAnnotations. * ComparisonProperty placeholder is now formatted like PropertyName * Translations of default error messages into other languages are now lazily-loaded * Added Slovenian translations of default error messages. * Added Icelandic translations of default error messages. * Added WithMessageArgument to the test helpers. * Add additional overload of SetValidator that takes a Func that receives the current property value. * ASP.NET Core: FluentValidationModelValidatorProvider and FluentValidationModelValidator are now public. * Work around a bug in ASP.NET Core's integration testing components that can cause ConfigureServices to run multiple times. * SourceLink integration. * {CollectionIndex} placeholder can now be accessed in child validators. * Additional ValidationException constructor that allows using both the default message and a custom one together. * ScalePrecisionValidator algorithm now matches SQL Server. * Additional overload of the When methods that contain the validation context. Full release notes can be found at https://github.com/FluentValidation/FluentValidation/blob/master/Changelog.txt