code.html: update to reflect that package names need not be unique
code.html: update to reflect that package names need not be unique

Fixes issue 1507.

R=golang-dev, ehog.hedge, rsc
CC=golang-dev
http://codereview.appspot.com/4160049

apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,ssrl/go,pombredanne/go-deleteme,ssrl/go,dsriram/golang,tv42/old-go,dsriram/golang,dsriram/golang,tv42/old-go,ssrl/go,tv42/old-go,apparentlymart/golang,dsriram/golang,tv42/old-go,pombredanne/go-deleteme,tv42/old-go,ssrl/go,gnanderson/go,tv42/old-go,gnanderson/go,gnanderson/go,pombredanne/go-deleteme,ssrl/go,apparentlymart/golang,pombredanne/go-deleteme,apparentlymart/golang,pombredanne/go-deleteme,gnanderson/go,gnanderson/go,apparentlymart/golang,pombredanne/go-deleteme,gnanderson/go,gnanderson/go,ssrl/go,dsriram/golang,ssrl/go,dsriram/golang,apparentlymart/golang,apparentlymart/golang,dsriram/golang