This patch fixes the OPAC view and holdability of items:

This patch fixes the OPAC view and holdability of items:

1. restores a check to itemtype.notforloan to set the norequests flag
2. changes improper boolean OR with AND for checking conditions of setting norequests
3. displays 'Not for loan' for item-level itypes when the itemtype is set to notforloan
4. restores items.notforloan values < 0 allowing holds (ordered items for instance)

We still need a notforhold flag set at the itemtype, and items level