Add Resource type

[chuwy]

It's a common task in IO related code to finalize some IO action, e.g. perform file.close or socket.close when those resources aren't needed anymore. In Http.lean we need to use it to handle connections. Later it can be a great candidate for a separate lib or stdlib.

In general it has the following structure:

1. The acquire action of IO α
2. The release action of α → IO Unit
3. use function of α → IO β
4. Monad instance

Examples:

1. Haskell
2. Scala

It's a bit problematic though given how much typical FP instances are in Mathlib4 - I suspect we might need to depend on it.

[algebraic-dev]

I want to break down all of the stuff that MathLib4 provides in a bunch of libraries :S. I'm not sure if it's the right choice but If you want to make it depend on mathlib4 while we don't have an equivalent it's ok.

[algebraic-dev]

I think that we can use https://github.com/joehendrix/lean-libuv for it :)