move to the new uproxy-lib world

This moves the repo to the new `uproxy-lib` world (4.x.x).

Summary:
* add per-module typescript definitions
* move samples under the modules-under-test
* add a `tsd/` tree
* update imports

This also kills the `copypaste` sample. I was planning to do that in my next merge but since it's a bit of work to migrate to the new build system, I opted to do it now. Also, you might point out that while the `chat` sample is under `pipe`, it doesn't actually use `pipe`. Well, my next pull request will make that clearer :-)

Tested by `grunt test` and manually exercising the sample apps.
Better to include what you use than include the tsd file. But I guess the point is that we probably need sym-link each directory in typings to do the merge rather than the whole third_party directory... good point, I'll file an issue... 
https://github.com/uProxy/uproxy/issues/314