Set up sync with Crowdin

[brecke]

Let's use Crowdin's cli tool for this. Then let's attach this tool to mocha tests for translation (instead of git cloning 3akai-ux).

Todos:

• Set up Crowdin's cli tool
• Attach it to mocha translation tests

Resources:

• Internationalization library for Svelte
• A Step-by-Step Guide to Svelte Localization with svelte-i18n v3