Removed unpack behaviour and use "runtimes" feature of nuget packages

[timyhac]

[jkoplo]

Ooh, does this work? Just read up on it.

[timyhac]

@jkoplo - I'm not sure.. It's been on "the list" since before this repo was public, but I'm not sure how it works, and whether it supports as many scenarios as the Extractor method. I figured that I'd get it to a level of completion that at least be tested.