Feature Request: config file

[rmoriz]

Scenario:

• multiple repositories
• Dockerfile.dapper in each repository
• same dapper cli option defaults for most repositories

Feature:

There should be logic to automatically pick up cli defaults from a config file, say dapper.yml. So a user has not to remember the CLI options and/or environment variables.

Looks like https://github.com/urfave/cli#values-from-alternate-input-sources-yaml-toml-and-others could be used very easily.