Demo for query storing

Change-Id: I947bcac841992c3f6cfd01ab337c265b0d01cb70
diff --git a/node_modules/is-png/index.js b/node_modules/is-png/index.js
new file mode 100644
index 0000000..81e6877
--- /dev/null
+++ b/node_modules/is-png/index.js
@@ -0,0 +1,15 @@
+'use strict';
+module.exports = function (buf) {
+	if (!buf || buf.length < 8) {
+		return false;
+	}
+
+	return buf[0] === 137 &&
+		buf[1] === 80 &&
+		buf[2] === 78 &&
+		buf[3] === 71 &&
+		buf[4] === 13 &&
+		buf[5] === 10 &&
+		buf[6] === 26 &&
+		buf[7] === 10;
+};