* config: add i18n

* docs: add chinese translation

* theming improvement for dropdown

The current format was linking to https://immerjs.github.io/immer/produce/return , which does not exist

`produce` function operates on `baseState` and produces `nextState`. Everywhere in this docs original state called `baseState`, but in the first snippet it's called `currentState`. I'm renaming it for consistency.

…#930)

* add article that explains how immerhin is built on top of immer

* Link to the author of immerhin article