compile goops submodules, goops.test now passes again

compile goops submodules, goops.test now passes again

* libguile/goops.c (get_slot_value, set_slot_value): While keeping the
  inlined getter/setter dispatch for closures, allow the getters and
  setters to be any kind of procedure.

* oop/goops.scm (compute-getters-n-setters): Relax the checks on
  getter/setter procedures, so that if a getter is a procedure but not a
  closure, we don't try to poke its arity.

* oop/goops/Makefile.am (SOURCES): Compile all the goops submodules!

* oop/goops/old-define-method.scm: Removed, in an act of housekeeping.

* oop/goops/compile.scm:
* oop/goops/dispatch.scm: Break a circular module dependency by making
  sure that (oop goops) is loaded when we go to compile submodules.

* oop/goops/compile.scm (compile-method/memoizer)
  (compile-method/memoizer+next): Allow a procedure without source
  through. This can happen with getter and setter lambdas that were
  compiled, and in that case there is no next-method call anyway. Ideally
  we should be able to specify compile-method for accessor methods...