Kher Yee

Results 2 issues of Kher Yee

The `mandate` field appears in the request to create/update a `Source` object, but it's not inside the response. It's helpful to include it inside the `Source` object, to know what...

This fix allows `Error` to be initialized with empty arguments without blowing up. The spec is still broken, please consider merging this [PR](https://github.com/chargebee/chargebee-ruby/pull/11) as well.