Add mise: Polyglot tool version manager like asdf

mise (pronounced "meez") or "mise-en-place" is a development environment
setup tool. The name refers to a French culinary phrase that roughly
translates to "setup" or "put in place". The idea is that before one
begins cooking, they should have all their utensils and ingredients
ready to go in their place.

mise does the same for your projects. Using its .mise.toml config file,
you'll have a consistent way to setup and interact with your projects no
matter what language they're written in.

(schmonz)