Log Message:
Update to 1.2.34:

version 1.2.34beta01 [November 27, 2008]
  Revised png_warning() to write its message on standard output by default
    when warning_fn is NULL. This was the behavior prior to libpng-1.2.9beta9.
  Fixed string vs pointer-to-string error in png_check_keyword().
  Added png_check_cHRM_fixed() in png.c and moved checking from pngget.c,
    pngrutil.c, and pngwrite.c, and eliminated floating point cHRM checking.
  Added check for zero-area RGB cHRM triangle in png_check_cHRM_fixed().
  In png_check_cHRM_fixed(), ensure white_y is > 0, and removed redundant
    check for all-zero coordinates that is detected by the triangle check.
  Revised png_warning() to write its message on standard output by default
    when warning_fn is NULL.

version 1.2.34beta02 [November 28, 2008]
  Corrected off-by-one error in bKGD validity check in png_write_bKGD()
    and in png_handle_bKGD().

version 1.2.34beta03 [December 1, 2008]
  Revised bKGD validity check to use >= x instead of > x + 1
  Merged with png_debug from libpng-1.4.0 to remove newlines.

version 1.2.34beta04 [December 2, 2008]
  More merging with png_debug from libpng-1.4.0 to remove newlines.

version 1.2.34beta05 [December 5, 2008]
  Removed redundant check for key==NULL before calling png_check_keyword()
    to ensure that new_key gets initialized and removed extra warning
    (Arvan Pritchard).

version 1.2.34beta06 [December 9, 2008]
  In png_write_png(), respect the placement of the filler bytes in an earlier
    call to png_set_filler() (Jim Barry).

version 1.2.34beta07 [December 9, 2008]
  Undid previous change and added PNG_TRANSFORM_STRIP_FILLER_BEFORE and
    PNG_TRANSFORM_STRIP_FILLER_AFTER conditionals and deprecated
    PNG_TRANSFORM_STRIP_FILLER (Jim Barry).

version 1.0.42rc01, 1.2.34rc01 [December 11, 2008]
  No changes.

version 1.0.42, 1.2.34 [December 18, 2008]
  No changes.