I have an rpy (py-R) package that I think is about ready to submit,
but it requires that R be updated to R1.6.1, so I started on updating
that and have a good cut at it, but there are some issues with
patching configure that I don't know the history of and am not sure
of the proper way to handle them.  I have a couple of the patch
files already updated, but need some help with the last (patch-ac
- I believe we can discard patch-ad)

In order to support rpy, the R package needs to build the R shared
library.  I added support for that and created a buildlink2 file
to reference the includes and lib (and patched the rpy setup.py)

However, should there be a separate package to build the R shared
library?