Update GraphicsMagick to 1.2.5.

1.2.5 (July 26, 2008)
=====================

Security Fixes:

  * None.

Bug fixes:

  * TIFF: Eliminated a memory leak in the codec support detection code.

  * JPEG: Removed over-write of image->client_data.

  * PNG: Fixed crash when writing PNG images with transparency and either
    optimize is requested, or the image is colormapped.

Feature improvements:

  * A file extension proxy module is used to automatically map from
    common camera raw format extensions to dcraw so that camera RAW
    images are loaded automatically using 'dcraw' or similar program
    as defined via the 'dcraw' entry in delegates.mgk.

  * ThresholdImage() uses a new implementation backported from the
    development version which attempts to avoid unnecessary image
    updates.

(obache)