add auth enabler

[Kirill-Garbar]

fixes #160

Changelog

Added

• [chart+kustomize]
  • what: Added downward API POD_NAMESPACE variable.
  • why: Necessary for operator to get secrets with certificates.
• [chart+kustomize]
  • what: Added get secrets permissions for operator namespace.
  • why: Necessary for operator to get secrets with certificates.
• [api]
  • what: Added helper functions to let getting settings easier.
  • why: Unify getting settings throughout the project code.
• [api]
  • what: Added ServerTrustedCASecret to spec.
  • why: Necessary to mount this certificate to let operator trust etcd cluster.
• [controller]
  • what: Added functionality to disable and enable auth, add root role, root user.
  • why: Necessary for the customer.

Changed

• [api]
  • what: Adjusted field descriptions for security fields.
  • why: Necessary to let customers know where we expect created secrets with certificates.