tutorial: update go_tutorial.html There's version skew with respect to the programs in doc/progs.
tutorial: update go_tutorial.html
There's version skew with respect to the programs in doc/progs.

R=golang-dev, rsc
CC=golang-dev
http://codereview.appspot.com/5433048

tav/go,tav/go,tav/go,tav/go,tav/go,tav/go,tav/go