Add awsAccessKeyId and awsSecretAccessKey to the ephemeral hdfs config
Add AWS access keys into the deploy template
Merge branch 'v3' of https://github.com/mesos/spark-ec2 into v3
Don't install httpd explicitly

This leads to the wrong version being installed. Instead we go with the version associated with ganglia.
Merge pull request #58 from danosipov/v3

Add S3 configuration
Merge pull request #1 from mesos/v3

merge upstream changes