Make --initial-password-prompt and -- [shell command] with sudo in it work together

[cmclaughlin]

If you set --initial-password-prompt and use Fabric to run an arbitrary shell command with sudo in front of it, you'll be prompted for a password on every host. It makes sense... in this case we're not using the sudo method, so I can see why I'm prompted. But it would be really nice if these options could be made to work together.