URLs are incorrect for node/add pages

If you create a content type with underscores in its machine-readable name, the URLs created by this module are incorrect.

For example, for a content type called my_content_type, the URL to create a new one should be node/add/my-content-type, not node/add/my_content_type.

I have a patch to correct this in the Popups: Add and Reference module, which I'll attach.