I think that 20% is too much. There are some gateways which allow only 60 chars to be sent. With this approach, it would reduce the message length up to 48 chars. That's really painful. Please change to 10%.

Also, I have a feeling that this setting might need some tweaking in the future. Currently it's quite hidden in the code. Please make it a method parameter of `findIndexOfCut` and define the value as an attribute at the beginning of `cutOutMessages` method.