Add hello world example

examples/HelloWorld.cpp

@@ -0,0 +1,14 @@
+#include "App.h"
+
+int main() {
+	/* Overly simple hello world app */
+	uWS::App().get("/*", [](auto *res, auto *req) {
+	    res->end("Hello world!");
+	}).listen(3000, [](auto *token) {
+	    if (token) {
+		std::cout << "Listening on port " << 3000 << std::endl;
+	    }
+	}).run();
+
+	std::cout << "Failed to listen on port 3000" << std::endl;
+}