====== Spring Java Mail Sender ======
Spring Java Mail Sender는 JavaMail을 사용한다.

<code xml>
<dependency>
  <groupId>javax.mail</groupId>
  <artifactId>mail</artifactId>
  <version>1.4.3</version>
</dependency>
</code>

  * http://www.javabeat.net/2008/11/email-integration-in-spring-framework/
  * http://www.mkyong.com/spring/spring-sending-e-mail-via-gmail-smtp-server-with-mailsender/