Add extension.name clarification
Add extension.name clarification

niboshi/chainer,ktnyt/chainer,ktnyt/chainer,keisuke-umezawa/chainer,ronekko/chainer,rezoo/chainer,jnishi/chainer,chainer/chainer,hvy/chainer,niboshi/chainer,keisuke-umezawa/chainer,keisuke-umezawa/chainer,wkentaro/chainer,niboshi/chainer,jnishi/chainer,ktnyt/chainer,okuta/chainer,jnishi/chainer,chainer/chainer,hvy/chainer,hvy/chainer,pfnet/chainer,chainer/chainer,wkentaro/chainer,wkentaro/chainer,okuta/chainer,chainer/chainer,tkerola/chainer,okuta/chainer,wkentaro/chainer,keisuke-umezawa/chainer,ktnyt/chainer,hvy/chainer,okuta/chainer,jnishi/chainer,niboshi/chainer