* Added PDF/A-2 and PDF/A-3 subsets A and B
It seems like PDF/A-2 and PDF/A-3 are not very different from PDF/A-1 as far as the A and B subsets are concerned (A requires tagging which PDFKit supports already). With this change, we can let the generated PDF present itself as PDF/A-2 or PDF/A-3.
* Updated docs and changelog for new PDF/A subsets
* Fixed an issue where ICC profile path can be wrong for built package but good for tests