Allow field name normalizers/denormalizers to be specified on a per-endpoint basis

[NatPri]

Pretty self-explanatory, but this would be a feature to allow clients to specify field name normalization/denormalizations on a per-endpoint basis. This would be useful in cases where (for instance) one endpoint picks PascalCase for their field names and another picks camelCase, and you want to standardize on one or the other in your code.

This could be worked-around using a responseTransformer and per-request denormalizers, but that feels pretty heavy for this specific type of transformation.

I have code for this and can submit a PR for it.