Improve readme

Author: richardcsantana

README.md

@@ -99,7 +99,10 @@ The following is the minimum needed code to send an email with the [/mail/send H
 
 ```java
 import com.sendgrid.*;
-import java.io.IOException;
+import com.sendgrid.helpers.mail.Mail;
+import com.sendgrid.helpers.mail.objects.Content;
+import com.sendgrid.helpers.mail.objects.Email;
+import com.sendgrid.helpers.mail.objects.Personalization;
 
 public class Example {
   public static void main(String[] args) throws IOException {
@@ -126,6 +129,40 @@ public class Example {
 }
 ```
 
+or using fluence interface
+
+```java
+import com.sendgrid.*;
+import com.sendgrid.helpers.mail.Mail;
+import com.sendgrid.helpers.mail.objects.Content;
+import com.sendgrid.helpers.mail.objects.Email;
+import com.sendgrid.helpers.mail.objects.Personalization;
+
+public class Example {
+    public static void main(String[] args) throws IOException {
+        Mail mail = new Mail()
+                .setFrom(new Email("[email protected]"))
+                .setSubject("Hello World from the SendGrid Java Library!")
+                .addPersonalization(new Personalization()
+                        .addTo(new Email("[email protected]")))
+                .addContent(new Content("text/plain", "Hello, Email!"));
+        SendGrid sg = new SendGrid(System.getenv("SENDGRID_API_KEY"));
+        Request request = new Request();
+        try {
+            request.method = Method.POST;
+            request.endpoint = "mail/send";
+            request.body = mail.build();
+            Response response = sg.api(request);
+            System.out.println(response.statusCode);
+            System.out.println(response.body);
+            System.out.println(response.headers);
+        } catch (IOException ex) {
+            throw ex;
+        }
+    }
+}
+```
+
 The `Mail` constructor creates a [personalization object](https://sendgrid.com/docs/Classroom/Send/v3_Mail_Send/personalizations.html) for you. [Here](https://github.com/sendgrid/sendgrid-java/blob/master/examples/helpers/mail/Example.java#L221) is an example of how to add to it.
 
 ### Without Mail Helper Class