Add help directly in the CLI

[jaydrogers]

👉 Describe the problem

• Users need to go to our documentation to figure out how to use proper syntax

👥 Problem evidence & reach

• All users who are getting started

🥰 Describe the "impact" on users?

• It's faster to work directly in the CLI than try to find help online

🏆 How to solve this problem

Here is a good example: https://github.com/fregante/chrome-webstore-upload-cli/blob/3e41b1024970b3dc42b37acdf8f77998d224a607/cli.js

💯 How do we validate the problem is solved?

• spin help will have an improved output
• Invalid commands will show helpful information rather than just saying "invalid command"