Bug 16937 [Revised] Remove "onclick" from the manage staged MARC records template

Bug 16937 [Revised] Remove "onclick" from the manage staged MARC records template

This patch revises the manage staged MARC records template, removing
"onclick" attributes from the markup and defining those events in the
script.

To test, apply the patch and go to Tools -> Manage staged MARC records.

- If necessary, stage a MARC file for import.
- Click the name of the staged file and then the "Import this batch into
  the catalog" button. The batch should be correctly imported.
- Return to the list of staged MARC files.
- Click the name of an imported file and then the "Undo import into
  catalog" button. The import should be reverted.
- Return to the list of staged MARC files.
- Click the "Clean" button for any record. Confirm that the batch is
  cleaned.
- For any cleaned record, click the "Delete" button. The batch should be
  deleted.

Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
Works as advertised

QA revision: Corrected class name so that "delete" button triggers the
correct warning.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>