configure first day of week for calendar and date-picker (#1952)

assets/js/KimaiTranslation.js

@@ -11,14 +11,25 @@
 
 export default class KimaiTranslation {
 
+    /**
+     * @param {Array<string, string>} translations
+     */
     constructor(translations) {
         this._translations = translations;
     }
 
+    /**
+     * @param {string} name
+     * @returns {string}
+     */
     get(name) {
         return this._translations[name];
     }
 
+    /**
+     * @param {string} name
+     * @returns {boolean}
+     */
     has(name) {
         return name in this._translations;
     }