- #7413 part 2 of 2
- add `ModelMetadata.Name` and `ParameterName`
- use `Name` instead of `PropertyName` in most cases
- update `ModelMetadata.ContainerType` and other property use
- choose using `MetadataKind` almost everywhere; support all possibilties
- usually parameter metadata was possible but not handled
- worst case was one or two potential NREs, especially `ContainerType.*` dereferences
- improve `MvcCoreLoggerExtensions` metadata handling
- add three new debug messages, one for type metadata and two for parameter metadata
- update `ModelMetadata.ContainerMetadata`, `ContainerType` and `PropertyName` doc comments
- no changes needed in Microsoft.AspNetCore.Mvc.ViewFeatures because parameters aren't viewed
nits:
- add missing `TestModelMetadataProvider.ForParameter(...)` method
- remove unused `EmptyModelMetadataProvider` instances in `ModelMetadataTest`
- refactor `ModelValidationResultComparer` out of DataAnnotationsModelValidatorTest`
- take VS suggestions, mostly related to variable inlining and object initializers
