glib: Make PrintPageRange preference available in API

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

poppler/poppler#290
6 jobs for glib-viewer-preferences in 19 minutes (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #214480
build

00:02:57

passed #214485
build_android

00:01:13

passed #214481
build_clang_libcpp

00:03:12

passed #214484
build_clazy

00:07:01

passed #214483
build_mingw64_fedora

00:19:00

passed #214482
build_ubuntu_16_04

00:03:15