Update aws.md

You have to update a bit since the configuration as is doesn't work. This addition will make more clear the pom configuration the users must have in order for the simple code of mentioned below works fine.
Can you make this line read more like the line above?

For example,

    In order to be able to use the SshjSshClientModule, you also need to get the dependency `org.jclouds.driver/jclouds-sshj`.