Bug 31076: Handle year limits with equal sign or colon

Bug 31076: Handle year limits with equal sign or colon

To test:
1 - Enable ES and index
2 - Set expandedSearchOption to 'show'
3 - Advanced search on staff and opac using Year field on staff and Publication date range on OPAC for:
    2005
    2005-
    -2005
    <2005
    >2005
    2005-2010
4 - Confirm ranges don't work on staff side, but do on opac
5 - Apply patch
6 - Repeat searches - they work on both staff and opac
7 - prove t/db_dependent/Koha/SearchEngine/Elasticsearch/QueryBuilder.t

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>