* Fix silly bugs in new linker, object.[ch].

* Allow modules to have arbitrary numbers of "extra" object files
  as well as their primary object file.  Initial requirement is
  that Prelude needs libHS_cbits.o/.dll as well as Prelude.o
  module(m).object is the primary object
  module(m).objectExtras are the extra objects
  module(m).objectExtraNames :: [Text] are their names.
  Modify machdep.c to assume that extra objects for module M
  live in the same directory as M's primary object.

* Stuff 130ish symbol names into the RTS symbol table, enough
  so that the whole Prelude can be linked.  That includes symbols
  in the C library needed by libHS_cbits.  This is very hacky
  and needs to be fixed properly.