Transform with Culture via ICulturedStringTransformer

[dahlbyk]

As proposed in #1061 (comment):

1. Adds support for input.Transform(culture, transformers)
2. Adds ICulturedStringTransformer : IStringTransformer
   

   Humanizer/src/Humanizer/Transformer/ICulturedStringTransformer.cs

   Line 16 in 3e23bb4

   string Transform(string input, CultureInfo culture);

   • New interface avoids a breaking change, but I think it's worth considering just updating IStringTransformer.Transform() to accept culture. Trivial for custom implementations to be updated with the new parameter, since they can just ignore culture if they don't care.
3. Updates To.LowerCase and such to return ICulturedStringTransformer (shouldn't be a breaking change, since it's assignable to IStringTransformer, with internal classes updated to implement the new overload.

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  • Haven't figured out how to test, as I don't know a language with upper/lower rules different from English.
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[dahlbyk]

Just noticed ApplyCase(LetterCasing) and Humanize(LetterCasing). Could reasonably update any/all to provide overloads that accept CultureInfo, too.

[dahlbyk]

Rebased onto main. Thoughts?