[poppler] multilayer PDF

[Valerio Messina]

an accurate description of what happen with Optional Content Groups is:

file1.pdf:pag.1_layers("A","B")
file2.pdf:pag.1_layers("C","D")

after 'pdfunite file1.pdf file2.pdf file.pdf' I got:

file.pdf:pag.1,2 but
pag.1:
1) list all layers("A","B","C","D")
2) file.pdf:pag.1 layers("A","B","C","D") are empty
3) contents of file1.pdf:pag.1_layers("A","B") always ON
pag.2:
1) list all layers("A","B","C","D")
2) file.pdf:pag.2 layers("A","B","C","D") are empty
3) contents of file2.pdf:pag.1_layers("C","D") always ON

Same happen with 0.55

Valerio