Color me gray--support for concurent duplicates

Up to this point, there has been no support for duplicate pages that exist at the same time (concurent duplicates). That has now changed.

The crpage and chtnm commands no longer check for duplicates. Also, when there are concurent duplicates, the link is painted gray.

Now when clicking on a gray link (or doing a cc to a topic with concurent duplicates), you are taken to the Journal view where alternate pages are listed. Links on the Journal view back to page view are always via uuid, so there is no confusion as to which page has been selected.