Security update for GraphicsMagick (important)

This update for GraphicsMagick fixes the following issues:

   * CVE-2017-12140: ReadDCMImage in coders\dcm.c has a ninteger
     signedness error leading to excessive memory consumption
     (bnc#1051847)
   * CVE-2017-14994: NULL pointer in ReadDCMImage in coders/dcm.c could
     lead to denial of service (bnc#1061587)
   * CVE-2017-12662: Memory leak in WritePDFImage in coders/pdf.c could
     lead to denial of service (bnc#1052758)
   * CVE-2017-14733: Heap overflow on ReadRLEImage in coders/rle.c could
     lead to denial of service (bnc#1060577)
   * CVE-2017-12644: Memory leak in ReadDCMImage in coders\dcm.c could
     lead to denial of service (bnc#1052764)
   * CVE-2017-10799: denial of service (OOM) can occur inReadDPXImage()
     (bnc#1047054)