Extract native modules uniquely

[kylecarbs]

https://github.com/codercom/nbin/blob/74da4b366f5c37ea47d83d3e73384e5a3307e00c/node.patch#L108

We don't check if the .node file extracted is different than the .node file in the binary.

We could do this by hashing the embedded .node file, or by checking size for now.

[code-asher]

We've decided to keep extracting them each time since it'll only happen once and might be less expensive than hashing anyway.