* doc/gnulib-tool.texi (Initial import): Update to match current

* doc/gnulib-tool.texi (Initial import): Update to match current
behavior with strdup module.
* lib/.cppi-disable: Remove strcase.h, strdup.h, strndup.h, strnlen.h.
* lib/memmem.h: Remove; all uses removed.  This is now done
by <string.h>.
* lib/mempcpy.h: Likewise.
* lib/memrchr.h: Likewise.
* lib/stpcpy.h: Likewise.
* lib/stpncpy.h: Likewise.
* lib/strcase.h: Likewise.
* lib/strchrnul.h: Likewise.
* lib/strdup.h: Likewise.
* lib/strndup.h: Likewise.
* lib/strnlen.h: Likewise.
* lib/strpbrk.h: Likewise.
* lib/strsep.h: Likewise.
* lib/strstr.h: Likewise.
* lib/strtok_r.h: Likewise.
* lib/string_.h: New file.
* lib/argp-namefrob.h: Don't include no-longer-existent include files.
Rely on <string.h> instead.
* lib/canon-host.c: Likewise.
* lib/chdir-long.c: Likewise.
* lib/concatpath.c: Likewise.
* lib/exclude.c: Likewise.
* lib/fchdir.c: Likewise.
* lib/getaddrinfo.c: Likewise.
* lib/getcwd.c: Likewise.
* lib/getsubopt.c: Likewise.
* lib/glob.c: Likewise.
* lib/hard-locale.c: Likewise.
* lib/iconvme.c: Likewise.
* lib/javacomp.c: Likewise.
* lib/mempcpy.c: Likewise.
* lib/memrchr.c: Likewise.
* lib/regex_internal.h: Likewise.
* lib/stpncpy.c: Likewise.
* lib/strcasecmp.c: Likewise.
* lib/strchrnul.c: Likewise.
* lib/strdup.c: Likewise.
* lib/striconv.c: Likewise.
* lib/striconveh.c: Likewise.
* lib/striconveha.c: Likewise.
* lib/strncasecmp.c: Likewise.
* lib/strndup.c: Likewise.
* lib/strnlen.c: Likewise.
* lib/strsep.c: Likewise.
* lib/strstr.c: Likewise.
* lib/strtok_r.c: Likewise.
* lib/userspec.c: Likewise.
* lib/w32spawn.h: Likewise.
* lib/xstrndup.c: Likewise.
* lib/mountlist.c (strstr): Remove decl.
* m4/string_h.m4: New file.
* m4/memmem.m4 (gl_FUNC_MEMMEM): Set HAVE_DECL_MEMMEM if necessary.
* m4/mempcpy.m4 (gl_FUNC_MEMPCPY): Set HAVE_MEMPCPY if necessary.
* m4/memrchr.m4 (gl_FUNC_MEMRCHR): Set HAVE_MEMRCHR
* m4/stpcpy.m4 (gl_FUNC_STPCPY): Set HAVE_STPCPY if necessary.
* m4/stpncpy.m4 (gl_PREREQ_STPNCPY): Set HAVE_STPNCPY if necessary.
* m4/strcase.m4 (gl_FUNC_STRCASECMP):
Set REPLACE_STRCASECMP if necessary.
(gl_FUNC_STRNCASECMP): Set HAVE_DECL_STRNCASECMP if necessary.
* m4/strchrnul.m4 (gl_FUNC_STRCHRNUL): Set HAVE_STRCHRNUL if necessary.
* m4/strdup.m4 (gl_FUNC_STRDUP): Set HAVE_DECL_STRDUP if necessary.
* m4/strndup.m4 (gl_FUNC_STRNDUP): Set HAVE_DECL_STRNLEN and
HAVE_DECL_STRDUP if necessary.
(gl_PREREQ_STRNLEN): Don't bother to check for strnlen decl,
since gl_FUNC_STRNDUP does that now.
* m4/strnlen.m4 (gl_FUNC_STRNLEN): Set HAVE_DECL_STRNLEN if necessary.
Check for decl here...
(gl_PREREQ_STRNLEN): ... not here.
* m4/strpbrk.m4 (gl_FUNC_STRPBRK): Set HAVE_STRPBRK if necessary.
* m4/strsep.m4 (gl_FUNC_STRSEP): Set HAVE_STRSEP if necessary.
* m4/strstr.m4 (gl_FUNC_STRSTR): Set REPLACE_STRSTR if necessary.
* m4/strtok_r.m4 (gl_FUNC_STRTOK_R): Set HAVE_DECL_STRTOK_R if
necessary.
* modules/string: New file.
* modules/memmem (Files): Remove special-purpose include file.
(Depends-on): Add string.
(Include): Include <string.h>, not the removed file.
* modules/mempcpy: Likewise.
* modules/memrchr: Likewise.
* modules/stpcpy: Likewise.
* modules/stpncpy: Likewise.
* modules/strcase: Likewise.
* modules/strchrnul: Likewise.
* modules/strdup: Likewise.
* modules/strndup: Likewise.
* modules/strnlen: Likewise.
* modules/strpbrk: Likewise.
* modules/strsep: Likewise.
* modules/strstr: Likewise.
* modules/strtok_r: Likewise.
* tests/test-dirname.c: Don't include "stdup.h", since
<string.h> now suffices.
* tests/test-memmem.c: Don't include "memmem.h", since
<string.h> now suffices.