Is your feature request related to a problem? Please describe.
As a user, I want to be able to easy initialise an ocibuilder.yaml specification file from a Dockerfile, which I can then add to and modify

Describe the solution you'd like
As a user, I would like to be able to run ocictl init --from-docker <PATH-TO-DOCKERFILE> which will generate my ocibuilder specification, taking advantage of the templating capabilities of ocibuilder.

Describe alternatives you've considered
N/A

Additional context
Will enable easier conversion from using standard Docker to ocibuilder instead