Bug 32099: Consistent classes for primary buttons: Assorted templates

Bug 32099: Consistent classes for primary buttons: Assorted templates

This patch makes changes the button markup in various assorted
templates so that all submit buttons and any buttons that should should
be styled as primary buttons have the Bootstrap class "btn btn-primary."

To test, apply the patch and view the following pages to confirm that
everything looks correct. In most cases there are no visible changes.

- Staff interface login
- Authorities -> Add/edit
- Authorities -> Merge
- ILL -> ILL requests
- Tools -> Patron lists
- Administration -> Manage plugins -> Upload plugin
- Point of sale
- Point of sale -> Transaction history
- Holds
- Suggestions
- Tags
- Calendar

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>