text: Title: k8s file-mounted secrets
  Body: In K8S, it is common to mount secrets to a file such as tmpfs.
  The typical format puts each secret into a separate file inside a mounted volume, where the key is the filename and the content is the value.
  Is there a way to achieve loading this in Dynaconf? 
  If not, what is the best way to add this functionality (using hooks or plugin, or contribute a PR?).
  