Make defaulting part of versioning codec
Make defaulting part of versioning codec

Most normal codec use should perform defaulting. DirectCodecs should not
perform defaulting. Update the defaulting_test to fuzz the list of known
defaulters. Use the new versioning.NewDefaultingCodec() method.

Kubernetes-commit: 1694cfb72dc70fdab57ad84c43b4f1a981c1d98a

kubernetes/api