This PR is built cumulatively on top of
two other PRs.

For confidence in review, only the third
commit is meant to be considered.

• Refactor data to settings (specificity)
• Refactor data structures into thier own module
• Refactor implement from_str trait for Target data

Renaming DeployFlake to target better represents the
semantic and making a target string from cli parse()able
perfects that angle of understanding.

Associating methods on the structs they belong to is a pattern
that will also help (in future PRs) to reduce the need for usage
of Copy.