Update MailjetServlet.java (#231)

Add region tags for documentation.

Author: carieshmarie

appengine/mailjet/src/main/java/com/example/appengine/mailjet/MailjetServlet.java

@@ -13,14 +13,15 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
+// [START mailjet_imports]
 package com.example.appengine.mailjet;
 
 import com.mailjet.client.MailjetClient;
 import com.mailjet.client.MailjetRequest;
 import com.mailjet.client.MailjetResponse;
 import com.mailjet.client.errors.MailjetException;
 import com.mailjet.client.resource.Email;
+// [END mailjet_imports]
 
 import org.json.JSONArray;
 import org.json.JSONObject;
@@ -32,6 +33,7 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+// [START app]
 @SuppressWarnings("serial")
 public class MailjetServlet extends HttpServlet {
   private static final String MAILJET_API_KEY = System.getenv("MAILJET_API_KEY");
@@ -65,3 +67,4 @@ public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOEx
     }
   }
 }
+// [END app]