Add internationalization (#114)

🇬🇧 and 🇮🇹

app/javascript/components/Board/NewPostForm.tsx

@@ -1,4 +1,5 @@
 import * as React from 'react';
+import I18n from 'i18n-js';
 
 import Button from '../shared/Button';
 
@@ -20,7 +21,7 @@ const NewPostForm = ({
   <div className="newPostForm">
     <form>
       <div className="form-group">
-        <label htmlFor="postTitle">Title</label>
+        <label htmlFor="postTitle">{I18n.t('board.new_post.title')}</label>
         <input
           type="text"
           value={title}
@@ -33,7 +34,7 @@ const NewPostForm = ({
         />
       </div>
       <div className="form-group">
-        <label htmlFor="postDescription">Description (optional)</label>
+        <label htmlFor="postDescription">{I18n.t('board.new_post.description')}</label>
         <textarea
           value={description}
           onChange={e => handleDescriptionChange(e.target.value)}
@@ -44,7 +45,7 @@ const NewPostForm = ({
         ></textarea>
       </div>
       <Button onClick={e => handleSubmit(e)} className="submitBtn d-block mx-auto">
-        Submit feedback
+        {I18n.t('board.new_post.submit_button')}
       </Button>
     </form>
   </div>