goinstall docs: fixed typos (Added mising closing quotes.)
goinstall docs: fixed typos
(Added mising closing quotes.)

R=golang-dev, gri
CC=golang-dev
http://codereview.appspot.com/1902049

Committer: Robert Griesemer <a6752097faebf1f02d80107d77a9be009089afe3@golang.org>
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go