godoc: remove paragraph tags around navigation div
godoc: remove paragraph tags around navigation div

R=golang-dev, iant
CC=golang-dev
http://codereview.appspot.com/4551051

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