Link from copies to library info page

Link from copies to library info page

In the absence of a specific lib.info_url org unit setting, link to the library
info page.

If we _do_ have a lib.info_url org unit setting, link from the library info
page to to the external web site.

Rather than wrapping everything in the table cell as the seller, focus
on the <a> and give it an explicit Library typeof attribute; then we can
offer up the name of the library as the name attribute, should the
crawler be too lazy to follow the link.

Signed-off-by: Dan Scott <dscott@laurentian.ca>
Signed-off-by: Dan Wells <dbw2@calvin.edu>