A review request for zsh-hoco

[Mikhail f. Shiryaev]

Hello. A year ago I've implemented the first version of the hosts' completion extension https://github.com/Felixoid/zsh-hoco. It uses my own caching invalidation and https://github.com/mafredri/zsh-async

Now I completely rewrote it to use zle -F and standard zsh caching functions _store_cache, _retrieve_cache, and _cache_invalid. Thanks to it, now the cache even will be shared between different shell instances.

Ideally, I'd like to have the function added here or in https://github.com/zsh-users/zsh/, that's why would like to kindly review the recent changes Felixoid/zsh-hoco#4