Log Message:
Update GraphicsMagick to 1.3.12.

1.3.12 (March 8, 2010)
==========================

Security Fixes:

  * Updated libpng Windows sources to 1.2.43 in order to resolve
    CVE-2010-0205 as it pertains to the GraphicsMagick Windows build.

Bug fixes:

  * Filter mode (write to stdout) was completely broken.

  * Should now compile with libpng 1.4.

  * Windows PerlMagick build identified itself as the wrong version.

New Features:

  * None

Feature improvements:

  * None

Performance Improvements:

  * None

Behavior Changes:

  * DCX output format is only written on request.  Previously the PCX
    coder would automatically switch to DCX format if multiple frames
    would be written.