single book, search results

@adam3smith, is there ever a requirement to cite a particular form of the ISBN? I'm thinking we should import ISBN-13 only and convert ISBN-10 to 13 where the latter is not available. Having multiple ISBNs makes little sense to me and I don't think it helps at all with citing. The WorldCat _search_ translator should replace the ISBN field with the value that was queried to get rid of all the other junk. The web translator is still going to be somewhat problematic.