https://rt.cpan.org/Ticket/Display.html?id=70530

* https://rt.cpan.org/Ticket/Display.html?id=70530
 - run_forked takes either scalar or arrayref
 - run_forked example
 - t/03_run-forked.t - several run_forked tests

* few tabs to spaces (since we generally don't have tabs in the module)