WebBasket: new 'move item' functionality

* Adds functionality to be able to move items between baskets.
  (closes #1547)

Signed-off-by: Krzysztof Lis <krzysztof.lis@cern.ch>
Reviewed-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'master' into next

* master:
  WebBasket: new 'move item' functionality