* src/deterministic/Cpp-det.sdf, src/grammar/Cpp.sdf,
	* src/pp/Cpp-pretty.pp, src/cpp-to-det/cpp-to-det.str,
	* src/det-to-cpp/det-to-cpp.str, src/pp/pp-cpp.str:
	Rename as...
	* src/deterministic/Cxx-det.sdf, src/grammar/Cxx.sdf,
	* src/pp/Cxx-pretty.pp, src/cxx-to-det/cxx-to-det.str,
	* src/det-to-cxx/det-to-cxx.str, src/pp/pp-cxx.str:
	...these.

	* configure.ac, src/Makefile.am, src/grammar/Cxx.sdf,
	* src/grammar/Makefile.am, src/deterministic/Cxx-det.sdf,
	* src/deterministic/Makefile.am, test/Makefile.am,
	* src/signature/Makefile.am, src/det-to-cxx/Makefile.am,
	* src/det-to-cxx/det-to-cxx.str, src/cxx-to-det/Makefile.am,
	* src/cxx-to-det/cxx-to-det.str, src/pp/pp-cxx.str, src/pp/Makefile.am:
	Rename cpp to cxx everywhere.