Change reference to listening port to 8080

The template used by scripts/new_webmachine.sh (wmskel) sets the
listening port to 8080 (in priv/templates/src/wmskel.app.src), not 8000
(as is used in the demo app).
Merge pull request #218 from derek121/port-used-in-docs

Change reference to listening port to 8080

Reviewed-by: reiddraper