feat: card locale translations (#509)

* Add Card Translations

* Add tests and documentation for `?lang` option

* Card Translations: update Italian

* Run Prettier

* Correct German Translations.

Co-authored-by: schmelto <30869493+schmelto@users.noreply.github.com>

* refactor: added i18n class to manage translation logic & improved code

* Make the new src/translations.js more concise

* Update translations.js

Co-authored-by: schmelto <30869493+schmelto@users.noreply.github.com>

* Revert 4175484d69289e4ee7283ab968b8e71c3c5d77df

* fix: overlap because of language length

Co-authored-by: lrusso96 <russo.1699981@studenti.uniroma1.it>
Co-authored-by: schmelto <30869493+schmelto@users.noreply.github.com>
Co-authored-by: Anurag <hazru.anurag@gmail.com>

readme.md

@@ -136,6 +136,7 @@ You can customize the appearance of your `Stats Card` or `Repo Card` however you
 - `hide_border` - Hides the card's border _(boolean)_
 - `theme` - name of the theme, choose from [all available themes](./themes/README.md)
 - `cache_seconds` - set the cache header manually _(min: 1800, max: 86400)_
+- `lang` - set the language in the card _(e.g. cn, de, es, etc.)_
 
 ##### Gradient in bg_color