Bug 11559: (QA followup) switch to new delimiter, fix minor issues

Bug 11559: (QA followup) switch to new delimiter, fix minor issues

This followup introduces a major change; instead of subfields starting
with '$<code><space>', they now start with '‡<code>'. The double-cross
character can be typed with Ctrl-D.

It also fixes the following:
  * Add UUID.pm dependency
  * Remove debugging call
  * Fix toLocaleFormat error reported by Nick Clemens
  * Ignore subfields that are marked as unrepeatable/mandatory AND
    ignored (tab is -1)
  * Mention lack of support for UNIMARC/NORMARC fixed fields in system
    preferences screen
  * Confirm when user creates new record and current record is modified
  * Perform better when importing gigantic record dump
  * Show "Edit" instead of "Import" and allow direct editing for local
    catalog records in search screen
  * Add "Keyboard shortcuts" help button to toolbar

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>