Add an option to ignore Ctrl+C/SIGINT #159

Hi. I have a script that spawns another program(probe-rs). That program handles Ctrl+C and prints out some useful information before exiting gracefully. When I press Ctrl+C in terminal(Windows), it seems that all 3 processes receive it(external program, my script and rust-script runner). I do handle it in my script using ctrlc in order to give time for probe to exit, but it seems rust-script exits and kills script and probe process immediately. However if I run the compiled script directly(from AppData) it works as expected. It would be nice if rust-script ignored Ctrl+C in order to let script handle it gracefully. Maybe when started with specific flag, but that might be a sane default option too since child programs exit on Ctrl+C anyway unless handled.