Multiple links in a user tag

mostly resolves #374

This is the basic implementation (supports multiple space-separated URLs), do you think there's enough demand to do it all pretty-like?
"Link 2" is kinda boring.  How about some pizzazz, like `escapeHTML(val).replace(/^https?:\/\/, '')`?  

and then a little CSS to make it look pretty:

    .RESDialogContents .authorDetail a { 
        max-width: 25em; 
        text-overflow: ellipsis; 
    }