This change also updates bind/testdata/*.golden. LGTM=crawshaw R=crawshaw CC=golang-codereviews https://golang.org/cl/167160043
LGTM=bradfitz, rsc R=rsc, bradfitz CC=golang-codereviews https://golang.org/cl/162710043
Details: http://golang.org/s/gobind LGTM=adonovan R=adonovan CC=golang-codereviews https://golang.org/cl/118240044