Update ozone ranger plugin to handle snapshots

This plugin needs to be updated to handle snapshots:

https://github.com/apache/ranger/blob/71809108fd106b664b6f9d53e0efd86d4c5cd039/plugin-ozone/src/main/java/org/apache/ranger/authorization/ozone/authorizer/RangerOzoneAuthorizer.java

If it is checking a snapshotted path, it should check if that path has an explicit policy.  If so, it should apply that policy.

Otherwise it should fall back to checking for a corresponding policy on the active filesystem path.