A hash function was declared in a .hxx file even though
	it was not templated.
	The makefile associated to the eps_removal bench was not generated.
	* include/vaucanson/misc/hash.hh,
	* include/vaucanson/misc/hash.hxx: make a hash function inline.
	* src/benchs/eps_removal/Makefile.am,
	* src/benchs/eps_removal/eps_removal-bench.cc,
	* src/benchs/generate_benchs.sh:
	 fix the generation of the related Makefile.