[MERGE-REQUEST] Improved `aggregated' typespec support

[Ludovic Courtès]

Hello,

The following patch is a followup to `patch-7' which implements the
`aggregated' typespec[0].  Basically, it (i) improves code generation
(in some cases, the `gw__scm_deps' variable was declared but unused),
(ii) significantly improves the test case for `aggregated', and (iii)
slightly modifies the semantics of `#:wcp-free-function'.

  patch-13
      Improved code gen. and test case for `aggregated';
      changed `#:wcp-free-function'.

The change (iii) basically consists in having `gw_wct_create ()' take a
cleanup function of type `size_t (*) (void *)' instead of
`size_t (*) (SCM)'.  This makes it independent of the underlying Scheme
implementation, and was needed to improve the test case for the
`aggregated'  typespec.

I just realize that I could and should have made (iii) a different patch
and I apologies for not doing so.

Again, I would very much welcome feedback.  :-)

Thanks,
Ludovic.

[0] http://lists.nongnu.org/archive/html/g-wrap-dev/2005-09/msg00006.html