doc/go1.3.txt: unicode upgrade to 6.3.0
doc/go1.3.txt: unicode upgrade to 6.3.0

LGTM=mpvl
R=mpvl
CC=golang-codereviews
https://codereview.appspot.com/65550044

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