sudo.bash: diagnose when the go tool is not in $PATH Fixes issue 4386.
sudo.bash: diagnose when the go tool is not in $PATH
Fixes issue 4386.

R=golang-dev, iant
CC=golang-dev
http://codereview.appspot.com/6854050

wesolows/golang-old,wesolows/golang,firebitsbr/golang-old,wesolows/golang-old,wesolows/golang,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old,firebitsbr/golang-old,firebitsbr/golang-old,wesolows/golang,wesolows/golang-old