1.1.0

• Changed implementation to create all children in separate process groups and send signals to the complete process group. This allows to terminate not only direct children but also sub-children. It makes it easier to handle the case of subchildren as their parent doesn't have to handle their termination. This is the same behavior than the one used by sh or bash, notably to send SIGINT.
• Added checks to ensure all zombie children or sub-children are properly reaped.