Update .gitignore
Update .gitignore

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