disposablestack

An ESnext spec-compliant `DisposableStack`, `AsyncDisposableStack`, `Symbol.dispose`, and `Symbol.asyncDispose` shim/polyfill/replacement that works as far down as ES3.

@seanalunni/explicit-resource-management-polyfill

Lightweight polyfill of the `Symbol.dispose` symbol and its implementation for `Iterator` (Which are the only things I personally need)