fmt: improve documentation for width and precision Fixes issue 7048.
fmt: improve documentation for width and precision
Fixes issue 7048.

LGTM=dominik.honnef
R=golang-codereviews, dominik.honnef
CC=golang-codereviews
https://codereview.appspot.com/74280044

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