Some meat in the readme

README.md

@@ -1,3 +1,22 @@
 # Java Rackspace Service Registry client
 
 Java client for Rackspace Service Registry.
+
+## Build and run tests
+
+	mvn install
+
+## Using the client
+
+### Registration and Heartbeat
+
+    Client client = new Client("MY_RAX_USER", "MY_RAX_API_KEY", Region.US);
+
+    Map<String, String> metadata = new HashMap<String, String>();
+    metadata.put("host", "127.0.0.1");
+    metadata.put("testdata?", "absolutely");;
+    metadata.put("version", "0u812");
+
+    SessionCreateResponse sessionResponse = client.sessions.create(15, metadata);
+
+    sessionResponse.getHeartbeater().start();