* NEWS: GNU make now recommended for VPATH builds.

* NEWS: GNU make now recommended for VPATH builds.
Mention that some macros are now documented to be obsolescent.
* doc/autoconf.texi:
Prefer "current" to "modern" to describe
currently-used (albeit perhaps old-fashioned) hosts.
Mention which ancient features no longer need to be worried about.
setgid -> set-group-ID
setuid -> set-user-ID (these are the Posix terms)
Fix some misuses of "only".
(AC_C_BACKSLASH_A, AC_C_CONST, AC_C_PROTOTYPES):
(AC_C_STRINGIZE, AC_C_VOLATILE, AC_FUNC_CLOSEDIR_VOID):
(AC_FUNC_GETPGRP, AC_FUNC_LSTAT, AC_FUNC_MEMCMP):
(AC_FUNC_SELECT_ARGTYPES, AC_FUNC_SETPGRP):
(AC_FUNC_SETVBUF_REVERSED, AC_FUNC_STAT, AC_FUNC_STRFTIME):
(AC_FUNC_STRNLEN, AC_FUNC_UTIME_NULL, AC_FUNC_VPRINTF):
(AC_HEADER_DIRENT, AC_HEADER_STAT, AC_HEADER_STDC):
(AC_HEADER_SYS_WAIT, AC_HEADER_TIME, AC_ISC_POSIX):
(AC_PROG_GCC_TRADITIONAL, AC_STRUCT_TM):
Mention that these macros are obsolescent.
(Installation Directory Variables): shall -> should
(File Descriptors): Mention that 0, 1, 2 might get reopened.
Mention that it's now safe to use 3 and 4.
(Limitations of Usual Tools): cp -r is now specified by Posix.
Omit longwinded and obsolescent discussion of cp -f.
Modernize discussion of expr, ls.
(Limitations of Make): Modernize discussion of VPATH builds.
Mention $? as a workaround in some cases.
* doc/install.texi (Basic Installation):
Mention "./configure; make; make install" first.  Be more
specific about why this file is generic.  Remove unnecessary
parens.  Remove misleading "only".  Remove obsolete advice
about csh.  Don't say "configure" takes awhile; say it
might take a while.  Suggest CFLAGS=-g rather than CFLAGS=-O2,
and CC=c99 rather than CC=c89, as these are blessed by current
Posix.  Recommend GNU make if doing a VPATH build.