Change eth-deposit package to TS

[TucksonDev]

First attempt to move one tutorial to TS (eth deposit). I only changed the require instructions to imports, and had to cast the first config variable to string.

It looks like the result when compiling is quite good. You can compile the file with yarn build , or see this gist => https://gist.github.com/TucksonDev/22efa85dc7fd0f0546b3a590bb9e496d

I added the needed packages to this tutorial's package.json, but ideally we would have them at the root level if we change all tutorials to TS.

[chrisco512]

LGTM

[TucksonDev]

Closing this one for now