from autoconf-2.62

to be consistent with the rest of the source files.

in pngset.c

outside of the PNG_READ|WRITE_ANCILLARY_CHUNK_SUPPORTED macros and
updated CHANGES and ANNOUNCE.  The definitions were actually relocated
in the previous commit but I forgot to mention it.

to PNG_HANDLE_AS_UNKNOWN to make it possible to build a libpng that can
use the png_set_keep_unknown_chunks() mechanism to ignore unused chunks
without having to save unknown chunks.

of color samples in the tRNS chunk.

about calling png_set_IHDR() multiple times and about the order
of color samples in the tRNS chunk.

about using png_set_io_ptr() in configure scripts for detecting libpng

to add PNG_NO_READ_SWAP, PNG_NO_WRITE_SWAP

and "else statement;" into two lines.

Because of many cosmetic changes, drop back to beta and do rc01 later.

Evidently the fix didn't go into the real master copy.

"pngminus" should be "gregbook"

(README, gather.sh, makefile.std, and pngusr.h)

also minor editing of encoder/pngusr.h and decoder/pngusr.h

Only png_read_finish_row() can be omitted.

This stuff should be handled in the APNG fork.

This should be handled in the APNG fork, not in libpng proper.