Bug 30434: Convert catalog merge page tabs to Bootstrap

Bug 30434: Convert catalog merge page tabs to Bootstrap

This patch updates the catalog merge template so that it uses Bootstrap
tabs instead of jQueryUI. Some JavaScript is modified to accommodate the
new DOM structure.

The patch also makes a minor HTML correction, adding a missing "</ol>".

To test, apply the patch and search the catalog in the staff client.

- In the search results, check the checkbox for two records.
- Choose Edit -> Merge records.
- Click next to accept the merge reference selection.
- On the next page you should see two tabs under "Source records."
  Confirm that they work correctly.
- All checkboxes in the first tab should be checked by default.
- Confirm that tag and subfield selection still works correctly.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>