Add Google CloudDNS support to external-dns

- Add Google CloudDNS support to external-dns
  Metadata should look like
    kubernetes:
    common:
      addons:
        externaldns:
          enabled: True
          provider: google
          google_options:
            key:
            project:

Change-Id: Ic468089dc1fdd558194cc5141a8ed4b702c9de59
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
4 files changed