Fix --config resolving

[ReDrUm]

Stricter CLI exposes the -c and --config flags, similar to ESLint, however they weren't functional.

The default behaviour of not specifying a config path correctly finds the root config, but when specifying a path it'd throw an error claiming to not find the file.

Additionally, fixes an import to fix allow opting into the debug logger.

const logger = isCi ? getNullLogger() : getDebugLogger();

[ReDrUm]

What's the process for contributing, versioning, and publishing now that this is open source? I don't see a guide in the README.md.

[Li0liQ]

TravisCI is configured to publish a new version once it finds a new tag (see https://github.com/atlassian/stricter/blob/master/.travis.yml#L20-L21).
I.e. you merge the changes into master, update the version in package.json and add a changelog. After that you create and push a new tag. Once it lands, TravisCI will deploy a new version automatically.

[marcodejongh]

@Li0liQ You better not rotate your npm keys then, or did you use an Atlassian bot user for publishing?