Core scraper & keep in sync with core for 0.10 and 0.11 to use with readable-stream

@substack would you consider giving me commit & publish rights of this package? If so, I'd like to use it as a dependency of readable-stream to keep things stable. The main problem is that 0.8 doesn't have `StringDecoder#end` and the current workaround in readable-stream@1.0.x (streams2) is to check for it and discontinue proper processing. An alternative would be to patch `StringDecoder` if it doesn't have `end()` but I'd rather not take that approach.

If you're happy with me maintaining this module, I'll keep it in sync with node stable and unstable and sync the version numbers (0.10.24 -> 0.10.24 and 0.11.10 -> 0.11.10) so there would be at least 2 active branches. Then I'd link the versions to the two active readable-stream branch releases.

As you can see, I've added a scraper, basically the same one I'm using in readable-stream. It'll grab the correct version and the tests that go along with it.