envkernel.sh: Don't drop parameters in run-script

Pass parameters after the script name to the script itself.

I'm not entirely happy with the printf '"%s" ' pseudo-escape, but %q isn't available in POSIX and it covers the likely cases (like a space in a parameter), and doesn't require squeezing a full escape function into the alias. The alias itself runs in Bash on my system, but the existing code seems to try to work with different shells. I'd be happy to hear about better options. (This has been solved, see discussion below.)