Feat
- **cli**: enable displaying all traceback for CommitizenException when --debug flag is used
Refactor
- **exception**: rename MissingConfigError as MissingCzCustomizeConfigError
- **exception**: Rename CommitFailedError and TagFailedError with Bump prefix
- **commands/init**: add test case and remove unaccessible code
- **exception**: move output message related to exception into exception
- **exception**: implement message handling mechanism for CommitizenException
- **cli**: do not show traceback if the raised exception is CommitizenException
- introduce DryRunExit, ExpectedExit, NoCommandFoundError, InvalidCommandArgumentError
- use custom exception for error handling
- **error_codes**: remove unused NO_COMMIT_MSG error code