Merge del-cli

[chrisblossom]

Would you accept a PR that merges del-cli into this library? I often find myself having to require both del and del-cli as a dependency and think it would be a lot nicer to have this in one package.

[sindresorhus]

No, it's split for some good reasons:

• Users of del should not have to pay for CLI-related dependencies.
• From experience, many people missed the CLI part when I had them in one module.
• The readme gets noisy when it has to document both the API and CLI part.
• Very few use both at the same time.

See sindresorhus/ama#17 for more.