#206 - Added more projection examples in JPA.

Added another one that shows projections can be wrapped into an Optional.

jpa/example/src/test/java/example/springdata/jpa/projections/CustomerRepositoryIntegrationTest.java

@@ -134,4 +134,9 @@ public class CustomerRepositoryIntegrationTest {
 
 		assertThat(page.getContent().get(0).getFirstname(), is("Carter"));
 	}
+
+	@Test
+	public void appliesProjectionToOptional() {
+		assertThat(customers.findOptionalProjectionByLastname("Beauford").isPresent(), is(true));
+	}
 }