Bug 11279: Improve how a new quote of the day is selected

Bug 11279: Improve how a new quote of the day is selected

If there is a gap in the id sequence for the quotes table, it
is possible that no new quote will be selected. This will happen
particularly when a lot of the older quotes with low ids have been
deleted.

This patch improves the selection of a new quote.

To test:
- Load sample quotes
- Delete the first half of the quotes.
  Note: With 34 quotes, delete the quotes with ids from 1-17
- Activate the QuoteOfTheDay system preference
- Check if a quote is displayed in OPAC
- Reload the page a few times, no quote should be displayed
  Note: make sure you don't have a quote with the current
  date in your quotes table before running those tests
- Run 'perl t/db_dependent/Koha.t'
  Note: requires sample quotes!
- Apply patch
- Reload the OPAC start page
- Verify a quote was now picked
- Run 'perl t/db/dependent/Koha.t' again - all tests should still pass

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Patch modified to use "LIMIT 1 OFFSET ?" rather than "LIMIT ?, 1"; the
latter construction does not work in PostgreSQL.

Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>