Add message digest program sm3sum, it use OSCCA SM3 secure
hash (OSCCA GM/T 0004-2012 SM3) generic hash transformation.
* AUTHORS: Add sm3sum authors.
* README: Add sm3sum to programs list.
* bootstrap.conf: Add gnulib module 'crypto/sm3' used by sm3sum.
* build-aux/gen-lists-of-programs.sh: Add sm3sum to normal_progs.
* doc/coreutils.texi: Document sm3sum.
* man/.gitignore: Ignore sm3sum.1.
* man/local.mk: Generate man/sm3sum.1.
* man/sm3sum.x: sm3sum manual.
* src/.gitignore: Ignore sm3sum binary.
* src/local.mk: Build for sm3sum.
* src/md5sum.c: Add sm3sum algorithm.
* tests/local.mk: Add sm3sum.pl test.
* tests/misc/sm3sum.pl: sm3sum testcase.
* tests/misc/tty-eof.pl: Add sm3sum to algorithm list.