converted parse_pdf_to_text to py3
converted parse_pdf_to_text to py3

shencebebetterme/arxiv-sanity-preserver,shencebebetterme/arxiv-sanity-preserver,shencebebetterme/arxiv-sanity-preserver,shencebebetterme/arxiv-sanity-preserver,zhiyue/arxiv-sanity-preserver,zhiyue/arxiv-sanity-preserver,zhiyue/arxiv-sanity-preserver,karpathy/arxiv-sanity-preserver,karpathy/arxiv-sanity-preserver,karpathy/arxiv-sanity-preserver