Fixes documentation, and indentation of kernel code.
Fixes documentation, and indentation of kernel code.

Add brief summary of class definition.
Add spaces around operations.

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