doc/go1.4.html: document new subrepo import paths
doc/go1.4.html: document new subrepo import paths

LGTM=r, adg
R=adg, r, 0xjnml, dr.volker.dobler
CC=golang-codereviews
https://codereview.appspot.com/166980044

tv42/old-go,tv42/old-go,tv42/old-go,tv42/old-go,tv42/old-go,tv42/old-go,tv42/old-go