imagemagick - security update

This update fixes a large number of potential security problems due to
insufficient data validation when parsing different input
formats. Most of those potential security problems do not have a CVE
number assigned.

While the security implications of all of these problems are not all
fully known, it is highly recommended to update.

The update fixes the following identified vulnerabilities:

• CVE-2012-3437
  Incorrect validation of PNG buffer size, leading to DoS using
  specially crafted PNG files.
• CVE-2014-8354
  Out of bounds memory access in resize
• CVE-2014-8355
  Buffer overflow in PCX reader
• CVE-2014-8562
  Buffer overflow in DCM readers