* gh_test_repl.c (c_vector_test): same as gh_test_c.c

	* gh_test_repl.c (c_vector_test): same as gh_test_c.c

	* gh_test_c.c (c_vector_test): some improvements on the vector
	routines test.

	* gh.h (gh_vector): this used to exist but do the wrong thing.
	Now it (almost) does the right thing, though it takes a list
	instead of the individual arguments.  I need to see how it could
	be done right.
	(gh_list_to_vector): added this function as a macro.  Corresponds
	to Scheme's (list->vector ...).
	(gh_vector_to_list): added this function as a macro.  Corresponds
	to Scheme's (vector->list ...).

	* gh_data.c (gh_vector_ref): renamed from gh_vref to
	gh_vector_ref, so that it resembles the Scheme routines more.
	(gh_vector_set): renamed from gh_vset to gh_vector_set, so that it
	resembles the Scheme routines more.
	(gh_make_vector): this used to be (stupidly) called gh_vector().
	This is the right name, since it does the same thing as the Scheme
	(make-vector ...) procedure.