allow for granting userpoints for creation, but not for publication

Issue Summary

This module seems to act on the event of publishing content (in oposite to content-creation). This is a conceptual error I think. Publishing is an event which may be repeated undefinitely on behalf of the user. Especiall with the option "Deduct BAM when content is deleted or unpublished." unchecked, users are thereby enabled to create as much Userpoints as they like by just unpublishing and publishing content again and again.

To not break already running installation, I suggest to add a checkbox like e.g. "award Userpoints on node creation only (but not on node publishing)".