Import zlib-1.2.2 using new-style contrib handling.

Important changes since 1.1.4 include:
- New and improved inflate code, which is about 20% faster.
- New and improved crc32(), which is about 50% faster.
Switch to zlib 1.2.3, imported under contrib/zlib-1.2 to reduce impact
of latter updates. Remove fix the inflate bug, it is included already.
Delete old version of zlib from vendor branch.
Import zlib-1.2.5.
Update zlib from version 1.2.5 to 1.2.7 on vendor branch
zlib: Remove zconf.h

1) To facility merging the zlib vendor branch
2) zconf.h is generated, so it will move to the makefile framework
Merge branch 'vendor/ZLIB'
zlib: Add DragonFly README files

The README.DELETED used to be located on the vendor branch.
It was deleted there, updated, and placed on the master branch instead.
zlib: Upgrade from version 1.2.5 to version 1.2.7

===========================
 Changes since last update
===========================

Changes in 1.2.5.1 (10 Sep 2011)
- Update FAQ entry on shared builds (#13)
- Avoid symbolic argument to chmod in Makefile.in
- Fix bug and add consts in contrib/puff [Oberhumer]
- Update contrib/puff/zeros.raw test file to have all block types
- Add full coverage test for puff in contrib/puff/Makefile
- Fix static-only-build install in Makefile.in
- Fix bug in unzGetCurrentFileInfo() in contrib/minizip [Kuno]
- Add libz.a dependency to shared in Makefile.in for parallel builds
- Spell out "number" (instead of "nb") in zlib.h for total_in, total_out
- Replace $(...) with `...` in configure for non-bash sh [Bowler]
- Add darwin* to Darwin* and solaris* to SunOS\ 5* in configure [Groffen]
- Add solaris* to Linux* in configure to allow gcc use [Groffen]
- Add *bsd* to Linux* case in configure [Bar-Lev]
- Add inffast.obj to dependencies in win32/Makefile.msc
- Correct spelling error in deflate.h [Kohler]
- Change libzdll.a again to libz.dll.a (!) in win32/Makefile.gcc
- Add test to configure for GNU C looking for gcc in output of $cc -v
- Add zlib.pc generation to win32/Makefile.gcc [Weigelt]
- Fix bug in zlib.h for _FILE_OFFSET_BITS set and _LARGEFILE64_SOURCE not
- Add comment in zlib.h that adler32_combine with len2 < 0 makes no sense
- Make NO_DIVIDE option in adler32.c much faster (thanks to John Reiser)
- Make stronger test in zconf.h to include unistd.h for LFS
- Apply Darwin patches for 64-bit file offsets to contrib/minizip [Slack]
- Fix zlib.h LFS support when Z_PREFIX used
- Add updated as400 support (removed from old) [Monnerat]
- Avoid deflate sensitivity to volatile input data
- Avoid division in adler32_combine for NO_DIVIDE
- Clarify the use of Z_FINISH with deflateBound() amount of space
- Set binary for output file in puff.c
- Use u4 type for crc_table to avoid conversion warnings
- Apply casts in zlib.h to avoid conversion warnings
- Add OF to prototypes for adler32_combine_ and crc32_combine_ [Miller]
- Improve inflateSync() documentation to note indeterminancy
- Add deflatePending() function to return the amount of pending output
- Correct the spelling of "specification" in FAQ [Randers-Pehrson]
- Add a check in configure for stdarg.h, use for gzprintf()
- Check that pointers fit in ints when gzprint() compiled old style
- Add dummy name before $(SHAREDLIBV) in Makefile [Bar-Lev, Bowler]
- Delete line in configure that adds -L. libz.a to LDFLAGS [Weigelt]
- Add debug records in assmebler code [Londer]
- Update RFC references to use http://tools.ietf.org/html/... [Li]
- Add --archs option, use of libtool to configure for Mac OS X [Borstel]

Changes in 1.2.5.2 (17 Dec 2011)
- fix ld error: unable to find version dependency 'ZLIB_1.2.5'
- use relative symlinks for shared libs
- Avoid searching past window for Z_RLE strategy
- Assure that high-water mark initialization is always applied in deflate
- Add assertions to fill_window() in deflate.c to match comments
- Update python link in README
- Correct spelling error in gzread.c
- Fix bug in gzgets() for a concatenated empty gzip stream
- Correct error in comment for gz_make()
- Change gzread() and related to ignore junk after gzip streams
- Allow gzread() and related to continue after gzclearerr()
- Allow gzrewind() and gzseek() after a premature end-of-file
- Simplify gzseek() now that raw after gzip is ignored
- Change gzgetc() to a macro for speed (~40% speedup in testing)
- Fix gzclose() to return the actual error last encountered
- Always add large file support for windows
- Include zconf.h for windows large file support
- Include zconf.h.cmakein for windows large file support
- Update zconf.h.cmakein on make distclean
- Merge vestigial vsnprintf determination from zutil.h to gzguts.h
- Clarify how gzopen() appends in zlib.h comments
- Correct documentation of gzdirect() since junk at end now ignored
- Add a transparent write mode to gzopen() when 'T' is in the mode
- Update python link in zlib man page
- Get inffixed.h and MAKEFIXED result to match
- Add a ./config --solo option to make zlib subset with no libary use
- Add undocumented inflateResetKeep() function for CAB file decoding
- Add --cover option to ./configure for gcc coverage testing
- Add #define ZLIB_CONST option to use const in the z_stream interface
- Add comment to gzdopen() in zlib.h to use dup() when using fileno()
- Note behavior of uncompress() to provide as much data as it can
- Add files in contrib/minizip to aid in building libminizip
- Split off AR options in Makefile.in and configure
- Change ON macro to Z_ARG to avoid application conflicts
- Facilitate compilation with Borland C++ for pragmas and vsnprintf
- Include io.h for Turbo C / Borland C++
- Move example.c and minigzip.c to test/
- Simplify incomplete code table filling in inflate_table()
- Remove code from inflate.c and infback.c that is impossible to execute
- Test the inflate code with full coverage
- Allow deflateSetDictionary, inflateSetDictionary at any time (in raw)
- Add deflateResetKeep and fix inflateResetKeep to retain dictionary
- Fix gzwrite.c to accommodate reduced memory zlib compilation
- Have inflate() with Z_FINISH avoid the allocation of a window
- Do not set strm->adler when doing raw inflate
- Fix gzeof() to behave just like feof() when read is not past end of file
- Fix bug in gzread.c when end-of-file is reached
- Avoid use of Z_BUF_ERROR in gz* functions except for premature EOF
- Document gzread() capability to read concurrently written files
- Remove hard-coding of resource compiler in CMakeLists.txt [Blammo]

Changes in 1.2.5.3 (15 Jan 2012)
- Restore gzgetc function for binary compatibility
- Do not use _lseeki64 under Borland C++ [Truta]
- Update win32/Makefile.msc to build test/*.c [Truta]
- Remove old/visualc6 given CMakefile and other alternatives
- Update AS400 build files and documentation [Monnerat]
- Update win32/Makefile.gcc to build test/*.c [Truta]
- Permit stronger flushes after Z_BLOCK flushes
- Avoid extraneous empty blocks when doing empty flushes
- Permit Z_NULL arguments to deflatePending
- Allow deflatePrime() to insert bits in the middle of a stream
- Remove second empty static block for Z_PARTIAL_FLUSH
- Write out all of the available bits when using Z_BLOCK
- Insert the first two strings in the hash table after a flush

Changes in 1.2.6 (29 Jan 2012)
- Update the Pascal interface in contrib/pascal
- Fix function numbers for gzgetc_ in zlibvc.def files
- Fix configure.ac for contrib/minizip [Schiffer]
- Fix large-entry detection in minizip on 64-bit systems [Schiffer]
- Have ./configure use the compiler return code for error indication
- Fix CMakeLists.txt for cross compilation [McClure]
- Fix contrib/minizip/zip.c for 64-bit architectures [Dalsnes]
- Fix compilation of contrib/minizip on FreeBSD [Marquez]
- Correct suggested usages in win32/Makefile.msc [Shachar, Horvath]
- Include io.h for Turbo C / Borland C on all platforms [Truta]
- Make version explicit in contrib/minizip/configure.ac [Bosmans]
- Avoid warning for no encryption in contrib/minizip/zip.c [Vollant]
- Minor cleanup up contrib/minizip/unzip.c [Vollant]
- Fix bug when compiling minizip with C++ [Vollant]
- Protect for long name and extra fields in contrib/minizip [Vollant]
- Avoid some warnings in contrib/minizip [Vollant]
- Add -I../.. -L../.. to CFLAGS for minizip and miniunzip
- Add missing libs to minizip linker command
- Add support for VPATH builds in contrib/minizip
- Add an --enable-demos option to contrib/minizip/configure
- Add the generation of configure.log by ./configure
- Exit when required parameters not provided to win32/Makefile.gcc
- Have gzputc return the character written instead of the argument
- Use the -m option on ldconfig for BSD systems [Tobias]
- Correct in zlib.map when deflateResetKeep was added

Changes in 1.2.6.1 (12 Feb 2012)
- Avoid the use of the Objective-C reserved name "id"
- Include io.h in gzguts.h for Microsoft compilers
- Fix problem with ./configure --prefix and gzgetc macro
- Include gz_header definition when compiling zlib solo
- Put gzflags() functionality back in zutil.c
- Avoid library header include in crc32.c for Z_SOLO
- Use name in GCC_CLASSIC as C compiler for coverage testing, if set
- Minor cleanup in contrib/minizip/zip.c [Vollant]
- Update make_vms.com [Zinser]
- Remove unnecessary gzgetc_ function
- Use optimized byte swap operations for Microsoft and GNU [Snyder]
- Fix minor typo in zlib.h comments [Rzesniowiecki]

Changes in 1.2.7 (2 May 2012)
- Replace use of memmove() with a simple copy for portability
- Test for existence of strerror
- Restore gzgetc_ for backward compatibility with 1.2.6
- Fix build with non-GNU make on Solaris
- Require gcc 4.0 or later on Mac OS X to use the hidden attribute
- Include unistd.h for Watcom C
- Use __WATCOMC__ instead of __WATCOM__
- Do not use the visibility attribute if NO_VIZ defined
- Improve the detection of no hidden visibility attribute
- Avoid using __int64 for gcc or solo compilation
- Cast to char * in gzprintf to avoid warnings [Zinser]
- Fix make_vms.com for VAX [Zinser]
- Don't use library or built-in byte swaps
- Simplify test and use of gcc hidden attribute
- Fix bug in gzclose_w() when gzwrite() fails to allocate memory
- Add "x" (O_EXCL) and "e" (O_CLOEXEC) modes support to gzopen()
- Fix bug in test/minigzip.c for configure --solo
- Fix contrib/vstudio project link errors [Mohanathas]
- Add ability to choose the builder in make_vms.com [Schweda]
- Add DESTDIR support to mingw32 win32/Makefile.gcc
- Fix comments in win32/Makefile.gcc for proper usage
- Allow overriding the default install locations for cmake
- Generate and install the pkg-config file with cmake
- Build both a static and a shared version of zlib with cmake
- Include version symbols for cmake builds
- If using cmake with MSVC, add the source directory to the includes
- Remove unneeded EXTRA_CFLAGS from win32/Makefile.gcc [Truta]
- Move obsolete emx makefile to old [Truta]
- Allow the use of -Wundef when compiling or using zlib
- Avoid the use of the -u option with mktemp
- Improve inflate() documentation on the use of Z_FINISH
- Recognize clang as gcc
- Add gzopen_w() in Windows for wide character path names
- Rename zconf.h in CMakeLists.txt to move it out of the way
- Add source directory in CMakeLists.txt for building examples
- Look in build directory for zlib.pc in CMakeLists.txt
- Remove gzflags from zlibvc.def in vc9 and vc10
- Fix contrib/minizip compilation in the MinGW environment
- Update ./configure for Solaris, support --64 [Mooney]
- Remove -R. from Solaris shared build (possible security issue)
- Avoid race condition for parallel make (-j) running example
- Fix type mismatch between get_crc_table() and crc_table
- Fix parsing of version with "-" in CMakeLists.txt [Snider, Ziegler]
- Fix the path to zlib.map in CMakeLists.txt
- Force the native libtool in Mac OS X to avoid GNU libtool [Beebe]
- Add instructions to win32/Makefile.gcc for shared install [Torri]