Ability to control logging behavior

[erezrokah]

I've created a CircleCI custom resource using this library and it works pretty well, thank you :)

The only issue I have is that the library logs the event including the ApiToken property I pass to the custom resource. I would like to avoid logging sensitive data, or at least sanitize it.

I can probably monkey patch console.log but that seems very ugly.

I can create a pull request for this issue my self, but would like to decide first on a solution.
Possible solutions:

1. Ability to pass in a logger as an option.
2. Ability to pass log level as an option (also to disable library logging all together).
3. Ability to pass in a sanitize method.
4. Normalize the library logs with a common prefix to easily identify log messages.

I think a combination of 1+4 would probably cover most use cases.