publicAcl parameter for S3 uploads
Show ACL in upload task description, if public
Don't explicitly set private ACL
s/publicAcl/publicReadAcl/
publicReadAcl param documentation
Reinstate old bucket params
Rename S3UploadParams to S3AclParams
BONUS refactor: replace isDefined/apply with Option
Small tweak to S3Upload description
Make the publicReadAcl param work for WebApp uploadArtifacts action
Merge pull request #141 from guardian/s3-acl

ACL flag for S3 uploads