Re-write REStake script using Typescript

[tombeynon]

The current implementation of the REStake script was ripped out of the REStake UI code and moved into this repo. It's a few years old now, and was written very quickly. It's getting time to re-write the script almost entirely, but most importantly support Typescript.

We can either re-write the code entirely, which isn't as big a job as it might appear. There is a lot of code in this repo that isn't used, simply because it was extract from the REStake UI quickly. Alternatively we can just introduce Typescript as-is, then re-write it at a future date, which might be a bit simpler as Typescript will help with the refactor/rewrite when we get there.