Added more content for CSRF lesson

webgoat-lessons/csrf/src/main/resources/js/feedback.js

@@ -0,0 +1,7 @@
+webgoat.customjs.feedback = function() {
+    var data = {};
+    $('#csrf-feedback').find('input, textarea, select').each(function(i, field) {
+        data[field.name] = field.value;
+    });
+    return JSON.stringify(data);
+}