[libpng16] Revised the INSTALL document.
[libpng15] Revised INSTALL document.
[libpng15] Only mark text chunks as written after successfully writing them.
[libpng15] Removed "option WRITE_COMPRESSED_TEXT enables WRITE_TEXT" from

pnglibconf.dfa
[libpng15] Avoid out-of-bounds memory access in png_user_version_check().

Simplified and future-proofed png_user_version_check().
[libpng15] Imported from libpng-1.5.20beta01.tar
[libpng15] Quieted three "comparison is always false due to limited range"

compiler warnings in pngset.c
[libpng15] Bump version to 1.5.20beta02
[libpng15] Imported from libpng-1.5.20rc01.tar
[libpng15] The macros passed in the command line to Borland make were ignored if

similarly-named macros are already defined in makefiles. This behavior
is different from POSIX make and other make programs.  Surround the
macro definitions with ifndef guards (Cosmin).
[libpng15] Use memcpy instead of CopyMemory in the definition of png_memcpy.

The Borland C++ build breaks otherwise (Cosmin).
[libpng15] Imported from libpng-1.5.20rc02.tar
[libpng15] Added "-D_CRT_SECURE_NO_WARNINGS" to CFLAGS in

scripts/makefile.vcwin32.
Removed the obsolete $ARCH variable from scripts/makefile.darwin.
[libpng15] Imported from libpng-1.5.20rc03.tar
[libpng15] Imported from libpng-1.5.20.tar