Log Message:
Update to 1.5.8:

Version 1.5.8beta01 [January 15, 2011]
  Removed '#include config.h"' from contrib/libtests/pngvalid.c.  It's not
    needed and causes trouble for VPATH building.
  Moved AC_MSG_CHECKING([if libraries can be versioned]) later to the proper
    location in configure.ac (Gilles Espinasse).
  Fix bug in pngerror.c: some long warnings were being improperly truncated
    (bug introduced in libpng-1.5.3beta05).

Version 1.5.8rc01 [January 21, 2012]
  No changes.

Version 1.5.8rc02 [January 25, 2012]
  Fixed Min/GW uninstall to remove libpng.dll.a
  Conditionalize the install rules for MINGW and CYGWIN in CMakeLists.txt