Builtins have procedure properties

Builtins have procedure properties

* libguile/vm-builtins.h (FOR_EACH_VM_BUILTIN): Add arity information.
  (enum scm_vm_builtins):
* libguile/vm.c (scm_vm_builtin_ref):
  (scm_vm_builtin_name_to_index):
  (scm_vm_builtin_index_to_name): Adapt to macro interface change.
  (scm_init_vm_builtin_properties): New helper, sets procedure
  properties on builtins.
  (scm_bootstrap_vm): Just define the builtins here.  Later in the
  bootstrap we set their properties.
  (scm_sym_apply): Move definition here from expand.c.

* libguile/procprop.c (scm_init_procprop): Call
  scm_init_vm_builtin_properties.