(scm_make_u1vector): New, but only temporary.

(scm_make_u1vector): New, but only temporary.
(make_uve): Removed.
(scm_i_proc_make_vector, scm_i_proc_make_string,
scm_i_proc_make_u1vector): New.
(scm_init_unif): Initialize them.
(scm_i_convert_old_prototype): New.
(scm_make_uve): Use it to get the creator procedure.  Removed all
old code that created old-style uniform vectors.
(scm_array_p): Handle generic vectors.
(scm_dimensions_to_uniform_array): Do not fill new array with
prototype when that is a procedure.
(scm_list_to_uniform_array): Also accept a list of lower bounds as
the NDIM argument.
(scm_i_print_array): Print rank for shared or non-zero-origin
vectors.
(tag_proto_table, scm_i_tag_to_prototype, scm_i_read_array): New.
(scm_raprin1): Do not call scm_i_array_print for enclosed arrays,
which I do not understand yet.
(scm_array_prototype): Explicitely handle generic vectors.