Fix up how the built extension is constructed
Fix up how the built extension is constructed

It now builds/runs/passes tests.

pombredanne/dynd-python,michaelpacer/dynd-python,insertinterestingnamehere/dynd-python,cpcloud/dynd-python,ContinuumIO/dynd-python,mwiebe/dynd-python,insertinterestingnamehere/dynd-python,cpcloud/dynd-python,michaelpacer/dynd-python,insertinterestingnamehere/dynd-python,cpcloud/dynd-python,ContinuumIO/dynd-python,pombredanne/dynd-python,ContinuumIO/dynd-python,mwiebe/dynd-python,mwiebe/dynd-python,izaid/dynd-python,izaid/dynd-python,cpcloud/dynd-python,pombredanne/dynd-python,mwiebe/dynd-python,michaelpacer/dynd-python,izaid/dynd-python,insertinterestingnamehere/dynd-python,izaid/dynd-python,michaelpacer/dynd-python,ContinuumIO/dynd-python,pombredanne/dynd-python