[Ready for test/1.5.0] libpng (many)

[Charles Wilson]

libpng-1.0.15-2
libpng10-1.0.15-2
libpng10-devel-1.0.15-2

libpng-1.2.5-2
libpng12-1.2.5-2
libpng12-devel-1.2.5-2

No substantive changes; simply recompiled for 1.5.0 kernel.
--
  Charles Wilson
  cygwin at removespam cwilson dot fastmail dot fm