added play-framework project (#678)

* made changes to java reflection

* removed redundant method makeSound in Animal abstract class

* added project for play-framework article

play-framework/student-api/test/IntegrationTest.java

@@ -0,0 +1,25 @@
+import org.junit.*;
+
+import play.mvc.*;
+import play.test.*;
+
+import static play.test.Helpers.*;
+import static org.junit.Assert.*;
+
+import static org.fluentlenium.core.filter.FilterConstructor.*;
+
+public class IntegrationTest {
+
+    /**
+     * add your integration test here
+     * in this example we just check if the welcome page is being shown
+     */
+    @Test
+    public void test() {
+        running(testServer(3333, fakeApplication(inMemoryDatabase())), HTMLUNIT, browser -> {
+            browser.goTo("http://localhost:3333");
+            assertTrue(browser.pageSource().contains("Your new application is ready."));
+        });
+    }
+
+}