Fixes the knife command to have a different cwd
Fixes the knife command to have a different cwd

Adds on Salim's patch, but makes it so all calls to knife are from the
root of the workspace, avoiding a magic collision with the chef zero
config file.

retep998/delivery-cli,chef/delivery-cli,chef/delivery-cli,retep998/delivery-cli,retep998/delivery-cli,chef/delivery-cli,retep998/delivery-cli