The horizon repo and repos for plugins all have package.json but are
packaged using the python tools not npm tools. Assuming we might have
similar cases for puppet modules, this patch updates both cases to
ignore the other language packaging files when setup.py is present.
Change-Id: I61740a01a2289fed6ad5324c53b225d27fd3d6db
Signed-off-by: Doug Hellmann <doug@doughellmann.com>