When using Rook for managing Ceph we can use
Rook CRDs to create S3 buckets and users.
This PR adds bucket claim template to the
elasticsearch chart. Rook creates a bucket for
a bucket claim and also creates a secret
containing the credentials to get access to this
bucket. So we also add a snippet to expose
these credentials via environment variables to
containers where they are needed.
Change-Id: Ic5cd35a5c64a914af97d2b3cfec21dbe399c0f14
7f783dba51