roots with sudo < 1.7.0 fail with "cannot execute binary file"

jurt would fail with: /usr/bin/env: /usr/bin/env: cannot execute binary file

It happens because sudo -i on versions before 1.7.0 would not pass -c to the shell, rendering the command "/bin/bash /usr/bin/env".

The workaround for this issue is to set the following configuration option on older targets:

sudo-interactive-shell-command = sudo -i -- -c
