Fix#1691. PhpSpreadsheet allows the setting of different page size and orientation on each worksheet. It also allows the setting of page size and orientation on the PDF writer. It isn't clear which is supposed to prevail when the two are in conflict. In the cited issue, the user expects the PDF writer setting to prevail, and I tend to agree. Code is changed to do this, and handling things in this manner is now explicitly documented.
PhpSpreadsheet uses a default paper size of Letter, and a default orientation of Default (which Excel treats as Portrait). New static routines are added to change the default for sheets created subsequent to such calls. This could allow users to configure these defaults better for their environments. The new functions are added to the documentation.
580c741c8e