Allow deepcopy to tolerate generating packages under /vendor/
Allow deepcopy to tolerate generating packages under /vendor/

Adjust the output path of the package to be within the vendor directory,
even if the source path is normalized to the short path (i.e.
k8s.io/apimachinery/pkg/apis/meta/v1 should be generated under
k8s.io/kubernetes/vendor/k8s.io/apimachinery/pkg/apis/meta/v1).

A future change to gengo should handle this for all generators rather
than requiring per generator changes.

kubernetes/gengo