Remove testing.function_test from documents
Remove testing.function_test from documents

niboshi/chainer,keisuke-umezawa/chainer,chainer/chainer,keisuke-umezawa/chainer,hvy/chainer,tkerola/chainer,keisuke-umezawa/chainer,hvy/chainer,okuta/chainer,hvy/chainer,wkentaro/chainer,okuta/chainer,okuta/chainer,chainer/chainer,niboshi/chainer,pfnet/chainer,chainer/chainer,wkentaro/chainer,wkentaro/chainer,niboshi/chainer,chainer/chainer,wkentaro/chainer,niboshi/chainer,hvy/chainer,okuta/chainer,keisuke-umezawa/chainer