godoc: fix godoc.html template bug: correctly display package roots
godoc: fix godoc.html template bug: correctly display package roots

R=golang-dev, r
CC=golang-dev
http://codereview.appspot.com/4898042
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go