JIRA: https://jira.spring.io/browse/INTEXT-136
* Add `spring-cloud-aws` dependencies
* Remove all SES stuff, since Spring Cloud AWS provides implementations for `org.springframework.mail.MailSender`
* Add SES JavaMailSender Sample
* Add SES Spring Integration Sample
* Refactor DefaultAmazonSESMailSender to implement JavaMailSender and delegate to JavaMailSenderImpl rather than extending it
* Cleanup