def apply(cell)
      return false unless cell
      filter_items.each do |filter|
        return false if cell.value == filter.val
      end
      true
    end
Tells us if the row of the cell provided should be filterd as it
does not meet any of the specified filter_items or
date_group_items restrictions.
@param [Cell] cell The cell to test against items
TODO implement this for date filters as well!