Get the formatted cell value for the given row and column indices.

def pprint_cell(self, row, col):
        """
        Get the formatted cell value for the given row and column indices.
        """
        if col > 2:
            raise Exception("Only two columns available in a ItemTable.")
        elif row >= self.rows:
            raise Exception("Maximum row index is %d" % self.rows-1)
        elif col == 0:
            return self.dimensions('value')[row].pprint_label
        else:
            dim = self.get_dimension(row)
            heading = self.vdims[row]
            return dim.pprint_value(self.data.get(heading.name, np.NaN))