refactor

- move elixForms API logic to specific folder
- move everything else under Api folder

src/Api/Core/Response.php

@@ -0,0 +1,11 @@
+<?php
+namespace Core;
+
+class Response {
+    public function json($data, $status = 200) {
+        http_response_code($status);
+        header('Content-Type: application/json');
+        echo json_encode($data);
+        exit;
+    }
+}