Added simple echo arduino tester

Echo/Echo.ino

@@ -0,0 +1,13 @@
+void setup() {
+  Serial.begin(115200);
+}
+
+// the loop routine runs over and over again forever:
+void loop() {
+  while (Serial.available() > 0) {
+    Serial.write(Serial.read());
+  }
+}
+
+
+