* configure.ac: New tools added.
	* config/xt-rules.mk: New signature and constructor rules.
	* src/signature/Makefile.am: New file.
	* lib/Makefile.am: added distribution of the following files.
	* lib/stratego.pp: New file.
	* lib/stratego.pp.af: New file.
	* lib/sdf.cons.tbl: New file.