#26704 - Add parameter for strict null comparison
The Method PHPExcel_Worksheet::fromArray() takes a parameter $strictNullComparison which by default is false which has the effect that the cell data is not checked against the null value strictly, thus a value like bool(false) or int(0) will be treated like null, resulting in an empty cell.
Because this is very unfortunate in some situations, this PR adds a new parameter to \NetiPhpExcel\Service\PhpExcel\exportFunction() which can be used to set strict null comparison to true.
For purposes of BC, the default value is false.