Create new string util script.

assets/js/utils/string.js

@@ -0,0 +1,20 @@
+/* ----------------------------------------------------------------------------
+ * Easy!Appointments - Open Source Web Scheduler
+ *
+ * @package     EasyAppointments
+ * @author      A.Tselegidis <alextselegidis@gmail.com>
+ * @copyright   Copyright (c) Alex Tselegidis
+ * @license     https://opensource.org/licenses/GPL-3.0 - GPLv3
+ * @link        https://easyappointments.org
+ * @since       v1.5.0
+ * ---------------------------------------------------------------------------- */
+
+window.App.Utils.String = (function () {
+    function upperCaseFirstLetter(value) {
+        return value.charAt(0).toUpperCase() + value.slice(1);
+    }
+
+    return {
+        upperCaseFirstLetter
+    };
+})();