* src/digest.c: Organize HASH_ALGO_CKSUM to be table driven,
and amalgamate all digest algorithms.
(main): Parse all options if HASH_ALGO_CKSUM, and disallow
--tag, --zero, and --check with the traditional bsd, sysv, and crc
checksums for now.
* src/local.mk: Reorganize to include all digest modules in cksum.
* tests/misc/cksum-a.sh: Add a new test.
* tests/misc/b2sum.sh: Update to default to checking with cksum,
as b2sum's implementation diverges a bit from the others.
* tests/local.mk: Reference the new test.
* doc/coreutils.texi (cksum invocation): Adjust the summary to
identify the new mode, and document the new --algorithm option.
* man/cksum.x: Adjust description to be more general.
* man/*sum.x: Add [See Also] section referencing cksum(1).
* NEWS: Mention the new feature.
Note we don't support the --algorithm option of the
b2sum command in the external BLAKE2 project, as that
was deemed too confusing for users.
"BLAKE2b" was chosen as the default algorithm to use,
which is single threaded but performs well on 64 bit.
* src/blake2: CC0 source copied from external project.
* cfg.mk[VC_LIST_ALWAYS_EXCLUDE_REGEX]: Exclude blake2/
from syntax checks, make update-copyright, etc.
* src/local.mk: Reference the sources for b2sum,
and set the compilation flags.
* doc/coreutils.texi (b2sum invocation): Reference the
md5sum invocation node, and add descriptions of -l.
* tests/misc/b2sum.sh: Add new test.
* tests/local.mk: Reference new test.
* AUTHORS: Add new binary.
* README: Likewise.
* build-aux/gen-lists-of-programs.sh: Likewise.
* man/.gitignore: Likewise.
* scripts/git-hooks/commit-msg: Likewise.
* man/b2sum.x: New man page template.
* man/local.mk: Reference new template.
* src/.gitignore: Ignore new binaries.
* src/blake2/.gitignore: Ignore new build atrifacts.
* src/md5sum.c (usage): Describe the new -l option.
* NEWS: Mention the new program.
