Investigate if we need ACLs enabled on S3 buckets

[dchiquito]

For all our S3 buckets, we have this Object Ownership setting:

In all of our permission policies, we require that x-amz-acl be set to bucket-owner-full-control. This seems to have the net effect of disabling ACLs, but also requiring that clients set a header on any write request (and also making our policies more complex). I don't see any reason not to simply disable ACLs, but perhaps there is something I'm not thinking of.

@brianhelba ?

(CC @AlmightyYakob )

[danlamanna]

Duplicated by #137