add a route for sparkpi

This also places the common info text at the root index endpoint.

Author: elmiko

README.md

@@ -1,5 +1,5 @@
 # vertx-sparkpi
-A Java implementation of SparkPi using Vert.x 3 
+A Java implementation of SparkPi using Vert.x 3
 
 This application is an example tutorial for the
 [radanalytics.io](http://radanalytics.io) community. It is intended to be
@@ -32,5 +32,8 @@ You should have access to an OpenShift cluster and be logged in with the
 1. Visit the exposed URL with your browser or other HTTP tool, for example:
    ```bash
    $ curl http://`oc get routes/vertx-sparkpi --template='{{.spec.host}}'`
-   Pi is rouuuughly 3.1335
+   Java Vert.x SparkPi server running. Add the 'sparkpi' route to this URL to invoke the app.
+
+   $ curl http://`oc get routes/vertx-sparkpi --template='{{.spec.host}}'`/sparkpi
+   Pi is roughly 3.140480
    ```

src/main/java/io/radanalytics/examples/vertx/SparkPiVerticle.java

@@ -24,7 +24,7 @@ public class SparkPiVerticle extends AbstractVerticle {
   private static final Logger log = Logger.getRootLogger();
   private Properties prop = null;
 
-  // vertx-config has more exotic options using Futures 
+  // vertx-config has more exotic options using Futures
   // and AsyncResult handlers, but this is all we need
   private String loadJarProperty() {
     if (null==prop) {
@@ -65,6 +65,13 @@ public void run() {
     SparkPiProducer pi = new SparkPiProducer();
 
     router.route("/").handler(routingContext -> {
+      HttpServerResponse response = routingContext.response();
+      response
+          .putHeader("content-type", "text/html")
+          .end("Java Vert.x SparkPi server running. Add the 'sparkpi' route to this URL to invoke the app.");
+    });
+
+    router.route("/sparkpi").handler(routingContext -> {
       HttpServerResponse response = routingContext.response();
       response
           .putHeader("content-type", "text/html")