New: Formatter v2

[mysticatea]

• Rendered RFC
• Blocked by New: ESLint Class Replacing CLIEngine #40.

Summary

This RFC adds the custom formatter v2 that supports streaming based on #40.

Related Issues

• Show results for each file as eslint is running eslint#1098 - Show results for each file as eslint is running
• New: ESLint Class Replacing CLIEngine #40 - New: ESLint Class Replacing CLIEngine

[mysticatea]

I have noticed there is the practice that outputs progress bar into stderr. Because this proposal handles progress and results in the same stream, it cannot output progress to stderr.

[mysticatea]

Closing because I have withdrawn this proposal.