S3 dispatch does not work for generics defined inside an environment

That was my original plan as well, but managing and deploying dozens
of little packages that are all under active development is a
nightmare even with devtools. Just too much overhead, not to mention
that coming up with names that would not have namespace conflicts was
getting silly.

In the end, I wrote a package that implements lightweight python-like
modules for R and that has really improved my workflow. I hope to
publish this package later this year after I have cleaned it up a bit.