Bug 24847: Select AND by default in items search

Bug 24847: Select AND by default in items search

In items search form, when clicking on "New field" a new conjunction and search field are added.
It would save time to select AND conjunction by default, like it is in advanced search.

Test plan:
1) Go to items search
2) Click on  "New field"
3) Check that AND is selected

Signed-off-by: Sally <sally.healey@cheshiresharedservices.gov.uk>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>