Add OneGet

Windows 10 will include a package manager OneGet, here is a Scoop
manifest to get the latest "nightly"
* This most likely will need some tweaks as the PowerShell module
version changes I'm not sure if `Import-Module` will actually update the
module.
* Some resources about OneGet if your curious [Hacker
News](https://news.ycombinator.com/item?id=8524919) [Twitter
@PSOneGet](https://twitter.com/PSOneGet)
* As OneGet is fully extensible a plugin could be written to include
Scoop as a "Package Provider"