math: change Cosh test to close, not veryclose (needed on some x86 chips)
math: change Cosh test to close, not veryclose (needed on some x86 chips)

R=r
CC=Charlie Dorian, golang-dev
http://codereview.appspot.com/199054

pombredanne/go-deleteme,bdwalton/debian-golang,h8liu/golang,dsriram/golang,apparentlymart/golang,tianon/debian-golang,dsriram/golang,dsriram/golang,ssrl/go,tianon/debian-golang,bdwalton/debian-golang,pombredanne/go-deleteme,gnanderson/go,apparentlymart/golang,gnanderson/go,apparentlymart/golang,bdwalton/debian-golang,bdwalton/debian-golang,nightlyone/golang,nightlyone/golang,bdwalton/debian-golang,gnanderson/go,tv42/old-go,bdwalton/debian-golang,ssrl/go,h8liu/golang,dsriram/golang,apparentlymart/golang,tianon/debian-golang,pombredanne/go-deleteme,bdwalton/debian-golang,tv42/old-go,h8liu/golang,tianon/debian-golang,apparentlymart/golang,gnanderson/go,dsriram/golang,dsriram/golang,ssrl/go,dsriram/golang,tv42/old-go,gnanderson/go,ssrl/go,apparentlymart/golang,ssrl/go,pombredanne/go-deleteme,tianon/debian-golang,ssrl/go,nightlyone/golang,pombredanne/go-deleteme,nightlyone/golang,nightlyone/golang,apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,h8liu/golang,tv42/old-go,nightlyone/golang,tianon/debian-golang,tv42/old-go,gnanderson/go,h8liu/golang,tianon/debian-golang,pombredanne/go-deleteme,nightlyone/golang,bdwalton/debian-golang,h8liu/golang,tianon/debian-golang,h8liu/golang,gnanderson/go,ssrl/go,tv42/old-go