Split out substrate

[gavofyork]

Substrate is increasingly an independent project. Moreover, it will be licensed under some more permissive license, perhaps Apache2, perhaps MPL or possibly BSD+Patent (tbd by legal/enterprise strategy team). We'll want to repot it into a separate repo.

[chevdor]

Any work started on this?

[chevdor]

FYI: I started playing with https://github.com/chevdor/substrate to have a base for a PR for this issue.