doc: fix escaping in weekly.html
doc: fix escaping in weekly.html

R=golang-dev, dsymonds
CC=golang-dev
http://codereview.appspot.com/5306070

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