Add create-vm part to Go bindings

[axic]

Short tutorial: http://snowsyn.net/2016/09/11/creating-shared-libraries-in-go/

[axic]

@chfast I'm not sure what this was about, but I think the loader feature solves this.

[chfast]

This is about creating a Go VM interface that would make implementing VMs in Go easier. But I think the much more practical solution is do the Go VM first, and then see if there is any common code that can be extracted.

[axic]

Is there any work planned in this direction?

[chfast]

Adding EVMC API to geth's VM would be useful for testing and fuzzing, but this is not in the planning stage yet.