Log Message:
Update to 1.2.10:

Package change: install old compat library as libpngcompat (pkgsrc
specific, will probably be changed in the future). Makes package
handling quite a bit easier.

version 1.2.10beta1 [April 15, 2006]
  Renamed "config.h" to "png_conf.h" and revised Makefile.am \ 
to add
    -DPNG_BUILDING_LIBPNG to compile directive, and modified pngconf.h
    to include png_conf.h only when PNG_BUILDING_LIBPNG is defined.

version 1.2.10beta2 [April 15, 2006]
  Manually updated Makefile.in and configure.  Changed png_conf.h.in
    back to config.h.

version 1.2.10beta3 [April 15, 2006]
  Change png_conf.h back to config.h in pngconf.h.

version 1.2.10beta4 [April 16, 2006]
  Change PNG_BUILDING_LIBPNG to PNG_CONFIGURE_LIBPNG in config/Makefile*.

version 1.2.10beta5 [April 16, 2006]
  Added a configure check for compiling assembler code in pnggccrd.c

version 1.2.10beta6 [April 17, 2006]
  Revised the configure check for pnggccrd.c
  Moved -DPNG_CONFIGURE_LIBPNG into @LIBPNG_DEFINES@
  Added @LIBPNG_DEFINES@ to arguments when building libpng.sym

version 1.2.10beta7 [April 18, 2006]
  Change "exec_prefix=$prefix" to "exec_prefix=$(prefix)" in \ 
makefiles.

version 1.2.10rc1 [April 19, 2006]
  Ensure pngconf.h doesn't define both PNG_USE_PNGGCCRD and PNG_USE_PNGVCRD
  Fixed "LN_FS" typo in makefile.sco and makefile.solaris.

version 1.2.10rc2 [April 20, 2006]
  Added a backslash between -DPNG_CONFIGURE_LIBPNG and -DPNG_NO_ASSEMBLER_CODE
   in configure.ac and configure
  Made the configure warning about versioned symbols less arrogant.

version 1.2.10rc3 [April 21, 2006]
  Added a note in libpng.txt that png_set_sig_bytes(8) can be used when
    writing an embedded PNG without the 8-byte signature.
  Revised makefiles and configure to avoid making links to libpng.so.*

version 1.2.10 [April 23, 2006]
  Reverted configure to "rc2" state.