* examples/calc++/calc++-driver.cc, examples/calc++/calc++-driver.hh:

* examples/calc++/calc++-driver.cc, examples/calc++/calc++-driver.hh:
* examples/calc++/calc++-scanner.ll, examples/calc++/calc++.cc:
Remove from CVS.  These files are automatically generated.
* examples/extexi: Clarify that this file is now part of Bison,
not GNU M4, and that it works with any POSIX-compatible Awk.
* examples/calc++/Makefile.am (run_extexi): Remove; not used.
($(calc_extracted)): Renamed from $(calc_sources_extracted),
so that we also get calc++-parser.yy.  Geneate it.
Use $(AWK), not gawk, since any conforming Awk will do.
Put comment before action, since older 'make' can't handle comment
in action.
$(BUILT_SOURCES): List all built sources, not just some of them.
$(MAINTAINERCLEANFILES): Remove *.stamp, and all built sources.
$($(srcdir)/calc++-parser.stamp): Work even if POSIXLY_CORRECT.
$($(calc_sources_generated)): Remove unnecessary test for existence
of target.  (This had a shell syntax error anyway; a stray "x".)
(calc_extracted): List $(srcdir)/calc++-parser.yy, not
calc++-parser.yy.
* examples/.cvsignore, examples/calc++/.cvsignore: New files.