Install ${srcdir} changes from DJM.

Install ${srcdir} changes from DJM.
	* Makefile.in (SUBDIR_MAKEFILES): Add oldXMenu/Makefile to this
	list.
	(COPYDIR, COPYDESTS): Install files from both the etc directory in
	the source tree and the etc directory in the object tree.
	(${SUBDIR}): Pass the prefix variable down to submakes.
	(everywhere): Use `sed', not `/bin/sed'.  Not all systems have sed
	in /bin.
	(lib-src/Makefile, src/Makefile, oldXMenu/Makefile): Edit in
	values for srcdir and VPATH.
	(install): Add `v' flag to tar command.  Make sure that `dir'
	exists in ${srcdir}/info before copying it.  Remember that the man
	pages come from the source tree, not the object tree.
	* configure.in: Remove remarks saying that the --srcdir option
	doesn't work.
	Create the etc directory in the object tree.
	Recognize configuration names of the form *-sun-solaris*.
	Recognize sunos5 and solaris as operating system names.