This adds a new index privilege called `manage_dlm`. The `manage_dlm`
has permission to perform all DLM actions on an index, including put and
delete. It also adds the ability to call DLM get and explain to the
`view_index_metadata` existing index privilege.
This adds support for an index's index.lifecycle.origination_date setting in DLM. If an index has a
value for index.lifecycle.origination_date then it is used instead of the creation date or rollover
date (except in the case of the write index when the write index has not been rolled over yet).