Provide a means to convert a range, possibly with unions and possibly with intersections, into something that both Excel and PhpSpreadsheet can handle. Intersections are changed into unions of the individual cells which they comprise. With this change, Xls Writer now handles intersections (previously it would have thrown an Exception or created a corrupt worksheet if this was attempted), and Xlsx Writer works correctly (it seemed to before, but Excel didn't understand what it wrote). Worksheet::getConditionalRange and ::getConditionalStyles would previously have thrown an Exception when presented with an intersection, and will no longer do so.
**NOTE:** Intersection support is limited to Conditional ranges. Use of intersections in other contexts will usually not achieve the desired result.
oleibman