Bug 28720: (follow-up) Improve string translation

Bug 28720: (follow-up) Improve string translation

This patch fixes the following issues raised by QA:

- It modifies the markup so that "Add note" and "Edit note" can be
  translated more easily.
- It adds display of existing notes back to the table of checkouts.
- It adds to the table configuration so that a "plain" view of the notes
  (without buttons) is shown in print view and in CSV export.
- It improves handling of notes containing quotation marks which would
  previously have broken some edit interactions.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>