* NEWS: The configure command now warns you if you attempt to use

* NEWS: The configure command now warns you if you attempt to use
a directory whose name contains a special character like space,
newline, or "\".
* doc/autoconf.texi (Installation Directory Variables): Allow
"," in file names.  Do not use \@; it's not a portable regexp.
* bin/Makefile.am (edit): Likewise.
* lib/Makefile.am (edit): Likewise.
* tests/Makefile.am (edit): Likewise.
* tests/semantics.at: Likewise.
* tests/torture.at: Likewise.
* lib/autoconf/general.m4 (AC_ARG_PROGRAM): Likewise.
* lib/autoconf/status.m4 (_AC_SRCDIRS): Likewise.
* doc/autoconf.texi (File System Conventions): Warn about
unportable file names.
* lib/autoconf/general.m4 (_AC_INIT_DIRCHECK): New macro.
(AC_INIT): Use it.
(_AC_INIT_SRCDIR): Use ac_pwd rather than invoking pwd.
* lib/autoconf/status.m4 (_AC_OUTPUT_CONFIG_STATUS): Propagate
ac_pwd, and quote srcdir.
* lib/autotest/general.m4 (AT_INIT): Quote file name args.