Update from Gnulib

Update from Gnulib

This incorporates:
2018-06-29 regex: glibc does not use intprops.h
2018-06-28 regex: port to recently proposed glibc regex merge
2018-06-25 Continue to use spaces for indentation, not tabs
2018-06-25 manywarnings: Don't enable -Wjump-misses-init by default
2018-06-25 acl-internal.h: remove _GL_ATTRIBUTE_CONST on void function
2018-06-24 manywarnings: accommodate GCC 9: remove -Wchkp and -Wabi
2018-06-24 maint: clarify comments about sticky EOF
2018-06-24 af_alg: avoid hangs when reading from streams
2018-06-17 crypto: use byteswap
2018-06-17 getloadavg: Return 0 on MS-Windows without Cygwi
2018-06-17 getloadavg: Allow building on MS-Windows without Cygwin
* build-aux/config.guess, build-aux/config.sub, doc/misc/texinfo.tex:
* lib/acl-internal.c, lib/acl-internal.h, lib/get-permissions.c:
* lib/getloadavg.c, lib/gettimeofday.c, lib/md5.c, lib/pselect.c:
* lib/set-permissions.c, lib/sha1.c, lib/sha256.c, lib/sha512.c:
* lib/time.in.h, m4/getloadavg.m4, m4/gnulib-common.m4:
* m4/manywarnings.m4, m4/pthread_sigmask.m4, m4/vararrays.m4:
Copy from Gnulib.