Fixing #230; add a scrollbar to the PM popup dialog if necessary. This wasn't as easy as I thought. Had to wrap the PM text in a div with its styling (max-height and overflow). If I then resized the dialog, I'd get two scrollbars. So for now, made the dialog non-resizable.

div.weblinks-link-sort {
   padding-bottom: .5em;
}

ul.weblinks-link-options {
   margin: 0;
   padding-left: 0;
   list-style-type: none;
}

ul.weblinks-link-options li {
   display: inline;
   padding: 0 5px;
}