refactored javascript to ES6 classes (#759)

assets/js/KimaiConfiguration.js

@@ -0,0 +1,26 @@
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/*!
+ * [KIMAI] KimaiConfiguration: handling all configuration and runtime settings
+ */
+
+export default class KimaiConfiguration {
+
+    constructor(configurations) {
+        this._configurations = configurations;
+    }
+
+    get(name) {
+        return this._configurations[name];
+    }
+
+    has(name) {
+        return name in this._configurations;
+    }
+
+}