[Request] Add i18next-localstorage-backend

[Reya]

Library name: i18next-localstorage-backend
Library description: This is a i18next cache layer to be used in the browser. It will load and cache resources from localStorage and can be used in combination with the chained backend.
Git repository url: https://github.com/i18next/i18next-localstorage-backend
npm package name or url (if there is one): https://www.npmjs.com/package/i18next-localstorage-cache
License (List them all if it's multiple): MIT
Official homepage: https://github.com/i18next/i18next-localstorage-backend
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