Use `Progress`, and options to pass around the way messages are written.
Fixed some tiny issues in the code, but otherwise no functional changes.
To make colored output work with `docker run`, switched back image
generation to use volume mount for output (old mode is still
functioning, but it's not the default, and it works when docker is not
running on the same host).
Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
Support full configuration for image generation, including image
outputs, support most features (where applicable) for all image output
types, unify image generation process.
Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
