[libpng16] Bump version to 1.6.18beta01

ANNOUNCE

@@ -1,67 +1,30 @@
-Libpng 1.6.17 - March 26, 2015
+Libpng 1.6.18beta01 - March 26, 2015
 
-This is a public release of libpng, intended for use in production codes.
+This is not intended to be a public release.  It will be replaced
+within a few weeks by a public version or by another test version.
 
 Files available for download:
 
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   libpng-1.6.17.tar.xz (LZMA-compressed, recommended)
-   libpng-1.6.17.tar.gz
+   1.6.18beta01.tar.xz (LZMA-compressed, recommended)
+   1.6.18beta01.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lpng1617.7z  (LZMA-compressed, recommended)
-   lpng1617.zip
+   lp1618b01.7z  (LZMA-compressed, recommended)
+   lp1618b01.zip
 
 Other information:
 
-   libpng-1.6.17-README.txt
-   libpng-1.6.17-LICENSE.txt
-   libpng-1.6.17-*.asc (armored detached GPG signatures)
+   1.6.18beta01-README.txt
+   1.6.18beta01-LICENSE.txt
+   libpng-1.6.18beta01-*.asc (armored detached GPG signatures)
 
-Changes since the last public release (1.6.16):
+Changes since the last public release (1.6.17):
 
-  Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h
-  Corrected the width limit calculation in png_check_IHDR().
-  Removed user limits from pngfix. Also pass NULL pointers to
-    png_read_row to skip the unnecessary row de-interlace stuff.
-  Added testing of png_set_packing() to pngvalid.c
-  Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
-  Implement previously untested cases of libpng transforms in pngvalid.c
-  Fixed byte order in 2-byte filler, in png_do_read_filler().
-  Made the check for out-of-range values in png_set_tRNS() detect
-    values that are exactly 2^bit_depth, and work on 16-bit platforms.
-  Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
-  Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and
-    pngset.c to avoid warnings about dead code.
-  Do not build png_product2() when it is unused.
-  Display user limits in the output from pngtest.
-  Eliminated the PNG_SAFE_LIMITS macro and restored the 1-million-column
-    and 1-million-row default limits in pnglibconf.dfa, that can be reset
-    by the user at build time or run time.  This provides a more robust
-    defense against DOS and as-yet undiscovered overflows.
-  Added PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED macro, on by default.
-  Allow user to call png_get_IHDR() with NULL arguments (Reuben Hawkins).
-  Rebuilt configure scripts with automake-1.15 and libtool-2.4.6
-  Moved png_set_filter() prototype into a PNG_WRITE_SUPPORTED block
-    of png.h.
-  Avoid runtime checks when converting integer to png_byte with
-    Visual Studio (Sergey Kosarevsky)
-  Removed some comments that the configure script did not handle
-    properly from scripts/pnglibconf.dfa and pnglibconf.h.prebuilt.
-  Free the unknown_chunks structure even when it contains no data.
-  Updated CMakeLists.txt to add OSX framework, change YES/NO to ON/OFF
-    for consistency, and remove some useless tests (Alexey Petruchik).
-  Remove pnglibconf.h, pnglibconf.c, pnglibconf.pre, pnglibconf.dfn,
-    and pnglibconf.out instead of pnglibconf.* in "make clean" (Cosmin).
-  Fixed simplified 8-bit-linear to sRGB alpha. The calculated alpha
-    value was wrong.  It's not clear if this affected the final stored
-    value; in the obvious code path the upper and lower 8-bits of the
-    alpha value were identical and the alpha was truncated to 8-bits
-    rather than dividing by 257 (John Bowler).
 
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