Bug 9108: Followup: send the dateformat value from C4::Auth

Bug 9108: Followup: send the dateformat value from C4::Auth

- the dateformat value is send to all templates (from
  C4::Auth::get_template_and_user)
- remove all assignment of dateformat in all .pl files
- the DHTMLcalendar_dateformat variable is unused

Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Fixed conflicts:
 - opac/sco/sco-main.pl
 - reports/acquisitions_stats.pl
 - tools/cleanborrowers.pl

All tests pass, perlcritic problems appeared in some files
before and after these patches were applied.

Checked sorting in following pages:
- acqui/addorderiso2709.tt - list of staged imports in acq
- acqui/histsearch.tt - sorting of dates in acq search result list
- acqui/invoices.tt - billing date in list of invoices in acq
- acqui/lateorders.tt - list of late orders in acq
- acqui/ordered.tt - ordered titles and estimated costs for a fund
- acqui/parcels.tt - receive shipment page
- acqui/spent.tt - received titles and actual costs for a fund
...
- serials-search.tt - subscription search result list
...
- opac/sco/sco-main.tt - due dates in list of checked out items
- reports/acquisitions-stats.tt - date searches, display of dates
- tools/cleanborrowers.tt
- tools.holidays.tt - different views of dates library is closed,
  adding dates

Checked dates display according to system preference everywhere and
searching, entering dates etc. still worked as expected.
Signed-off-by: Jared Camins-Esakov <jcamins@cpbibliography.com>