* configure.ac (M4SH): AC_SUBST m4sh expander.

* configure.ac (M4SH): AC_SUBST m4sh expander.
* config/general.m4sh, config/getopt.m4sh: New files with factored
out functionality from...
* config/ltmain.in, libtoolize.in: ...here.  m4_include the shared
code, and call AS_SHELL_SANITIZE.  Also quote all `[' and `]' to
survive m4 run.
(func_serial): No need to double up m4sh quotes after a `#'.
(func_check_macros): Escape `dnl' to stop m4sh interpreting it as
a macro.
* tests/defs.in: New file expanded into tests/defs by autom4te.
* m4/libtool.m4 (_LT_DECL_EGREP): Also require fgrep for the tests
that use it.
* Makefile.am ($(top_srcdir)/config/ltmain.sh): Now built with
M4SH.
(libtoolize): Ditto.
* bootstrap: Set M4SH for call to make.
* HACKING: No need to sync to AS_SHELL_SANITIZE by hand any more.