* Minor Fix for AND/OR/XOR
These 3 fall into the set of functions where Excel treats string literals differently depending on whether they are passed to the function directly or as a cell reference. PhpSpreadsheet is updated to try to duplicate that logic. New tests are added. Some existing test results had to change as a result of this code change.
* Adopt A Suggestion From Mark Baker
Reduce if statements by adding functions.
oleibman