A utility type that allows you to defer dropping your data to a background
DeferDrop for details.
Inspired by [https://abramov.io/rust-dropping-things-in-another-thread]
Wrapper type that, when dropped, sends the inner value to a global background thread to be dropped. Useful in cases where a value takes a long time to drop (for instance, a windows file that might block on close, or a large data structure that has to extensively recursively trawl itself).