Ensure .cmd files always have DOS line endings

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
kill-shell: Add a comment to work around an obscure Jenkins issue

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Remove the Jenkins script again in favor of creating it on demand

This gets rid of executing it for every shell invocation on the user's
system.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>