Add --pages option in pdfium_test so it renders only some of the pages.
Add --pages option in pdfium_test so it renders only some of the pages.

The --pages option is set up to be 0-indexed.
--pages=<number> will render the specific page.
--pages=<number>-<number> will render the range of pages given.

Review-Url: https://codereview.chromium.org/2495333002

DrAlexx/pdfium,DrAlexx/pdfium,DrAlexx/pdfium,DrAlexx/pdfium