utils.lang.yaml: Extend lang.meta.Object to provide YAML 'wrapping'
utils.lang.yaml: Extend lang.meta.Object to provide YAML 'wrapping'

Objects constructed from YAML documents should now inherit from
lang.yaml.Object and specify the native class they wrap in the 'wraps'
class keyword argument.

     MyYamlObject(lang.yaml.Object, wraps=SomeObject): pass

The derived class will then be able to define the represent() method to
enable serialization of the wrapped object back to YAML.

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