go-playground/goplay/edit.html: incorporate "Other users" section to About screen.
go-playground/goplay/edit.html: incorporate "Other users" section to About screen.

LGTM=adg
R=golang-codereviews, adg
CC=golang-codereviews
https://codereview.appspot.com/67330046

Committer: Andrew Gerrand <395a7d33bec8475c9b83b7d440f141bcbd994aa5@golang.org>

Alexandr-Penkin/go-playground,stevelacy/go-playground,Alexandr-Penkin/go-playground,stevelacy/go-playground