Log Message:
Update graphics/ImageMagick and graphics/p5-PerlMagick to 6.2.6.8.

Changes to 6.2.8-8:
  * 'convert existing-image.png -background' no longer generates a fault.
  * -define pdf:use-cropbox=true actually works now.
  * Slight mods to magick/xwindow.c to compile under BEOS (path provided by
    henrimoi@hotma...).
  * #000000 improperly set the opacity channel (bug report and patch from
    digipete@shaw....).
  * Patch for OpenVMS compile support.

Changes to 6.2.6-7:
  * Added the 'Dispose' layers function to return the 'GIF dispose' images of
    an animation.
  * File is already closed, do not call fclose() on it in magick/blob.c.
  * PS3/EPS3 now writes a proper image mask when compression is None.
  * Patch to properly read interlaced GIF's.
  * DestroyMagick() is not always reliably available when atexit() unwinds.