Updating the Bind Attribute to do only have include properties.

cc: @pranavkm . @yishaigalatzer 
all-up, the four `ModelMetadata` properties set here should be lazily-initialized (like most `ModelMetadata` properties) and their handling should be divided between `ModelMetadata` and related classes in the usual manner i.e. _not_ special-cased here or in `AssociatedModelMetadata`.