It's the standard `OptionParser` message + the result of our rescue then abort a few lines above.

```Ruby
invalid option: -i

Please use --help for a listing of valid options
```

Note I cribbed this from the above, and I think `abort` is actually important because IIRC in some circumstances `exit` will print a stack trace (e.g. when invoked via rake?) whereas `abort` won't.