Support registry auth for FROM images

[kekru]

Hey, thanks for the plugin

we use a base image in our FROM command, that comes from a private registry.
As far as I see, the registry authentication is only for pushing.
When building, we get the error:

FROM reg.example.com/super-private:123

Error response from daemon:
Get https://reg.example.com/v2/super-private/manifests/123: unknown: Authentication is required

It would be great to support registry authentication for all operations.
Maybe with:

DefaultDockerClientConfig
  .createDefaultConfigBuilder()
  .withRegistryUrl("https:/reg.example.com/v2/")
  .withRegistryUsername("someone")
  .withRegistryPassword("hello")