Add --max-warnings cli option

[duaraghav8]

Description
--max-warnings [integer] CLI option lets a user specify the maximum number of warnings tolerable. If the number of warnings crosses this threshold, linter prints Warning threshold exceeded and returns a non-zero exit code.

Keep in mind that the value of this option is compared with the total number of warnings across all the files that the linter covers.

Use case
Keep the number of warnings in control.

Screenshots

Alternatives
Configure rules as errors instead of warnings

Comments

• If --fix-dry-run is used, linter should count the warnings that were temporarily fixed because dry run doesn't make those warnings go away from the code. Regardless of whether any warnings were fixed by dry run, all warnings should be counted.

• If --fix is used, linter should only count the warnings remaining after all fixes have been applied. Any warnings that --fix resolves need not be considered because they're removed permanently from the code.

Priority
MEDIUM