Allow case insensitive search on Item codes
Apparently there is an unique index on Item codes which is case insensitive, i.e. you can not create a different item with the same code with a different case. However the API doesn't allow case-insensitive search on item codes, which is really awkward. This is a big problem when you get an error when inserting a new item because of an earlier item with the same code but different case. It's very hard to find the original item in this case.