Threads

New to rust, I am trying to have my callback function be passed into my thread, this call back function will be called multiple times. However, it seems I can't have my cb shared between threads. ``F` cannot be shared between threads safely`

No file, test, or entry point is identified. Start by locating the callback and thread setup in node-bindgen, then reproduce the `F` cannot be shared between threads safely error. The intended threading behavior and a regression test need to be defined before completion can be judged.

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