- update to 10.47.13
    - fixes pnmtops
    - fix CVE-2007-2721 (#501451)
    - fix cmuwtopbm so that magic bytes test actually works
    - fix pamtojpeg2k (don't close stdout twice)
    - don't package patch backups in documentation
    - netpbm-progs package requires ghostscript
    - pgmtopbm should generate PBM, not PAM file
    - forwardport pnmmontage from 10.35 to make it work
    - fix pamstretch-gen
    - fix documentation for pamperspective and pbmtoepson
    - add missing man pages