Add flush option
Add flush option

cupy/cupy,AlpacaDB/chainer,niboshi/chainer,wkentaro/chainer,hvy/chainer,niboshi/chainer,wkentaro/chainer,keisuke-umezawa/chainer,niboshi/chainer,keisuke-umezawa/chainer,pfnet/chainer,keisuke-umezawa/chainer,chainer/chainer,benob/chainer,kashif/chainer,kikusu/chainer,rezoo/chainer,tkerola/chainer,chainer/chainer,AlpacaDB/chainer,kikusu/chainer,okuta/chainer,cupy/cupy,ktnyt/chainer,kiyukuta/chainer,ronekko/chainer,jnishi/chainer,benob/chainer,jnishi/chainer,hvy/chainer,okuta/chainer,niboshi/chainer,hvy/chainer,okuta/chainer,anaruse/chainer,hvy/chainer,chainer/chainer,delta2323/chainer,jnishi/chainer,cupy/cupy,ysekky/chainer,chainer/chainer,keisuke-umezawa/chainer,aonotas/chainer,wkentaro/chainer,jnishi/chainer,okuta/chainer,ktnyt/chainer,wkentaro/chainer,ktnyt/chainer,cupy/cupy,ktnyt/chainer