parsing_formula_on_open property

Indicates whether parsing the formula when reading the file.

Only applies for Excel Xlsx, Xltx, Xltm and Xlsm file because the formulas in the files are stored with a string formula.

@property
def parsing_formula_on_open(self):
    ...
@parsing_formula_on_open.setter
def parsing_formula_on_open(self, value):
    ...