Bug 30335: Add classes to invoice/credit tabs on patron accouting pages

Bug 30335: Add classes to invoice/credit tabs on patron accouting pages

To test:
1. Apply patch and go to the patron accounting page.
2. Notice the class names for each list element on the page.
3. You can use the following CSS to try hiding each of the tabs:

.transactions { display: none; }
.makepayment { display: none; }
.manualinvoice { display: none; }
.manualcredit { display: none; }

Signed-off-by: Rachael Laritz <rachael@inlibro.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>