glib: Make PrintPageRange preference available in API

Add poppler_document_get_print_page_range() so that applications which
use poppler's glib frontend can access this preference.

poppler/poppler#290
6 jobs from viewer-preferences in 12 minutes and 35 seconds (queued for 2 seconds)
Status Job ID Name Coverage
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passed #97350
build

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build_android

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build_clang_libcpp

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build_clazy

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build_gcc_49

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build_mingw64_fedora

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