* Improved handling of named ranges, although there are still some issues (names ranges using a union type with an overlap don't handle the overlap twice, which as the MS Excel approach to set overlaps as opposed to the mathematical approach which only applies overlap values once)
* Fix tests that misused space and comma as simple separators in cell ranges
Column indexes are always based on 1 everywhere in PhpSpreadsheet.
This is consistent with rows starting at 1, as well as Excel
function `COLUMN()`. It should also make it easier to reason about
columns and rows and remove any doubts whether a specific method is
expecting 0 based or 1 based indexes.
Fixes#273
Fixes https://github.com/PHPOffice/PHPExcel/issues/307
Fixes https://github.com/PHPOffice/PHPExcel/issues/476