Remove setuptools from install_requires
Remove setuptools from install_requires

When we use setup() for installation, module already depends on setuptools.

ktnyt/chainer,AlpacaDB/chainer,chainer/chainer,sinhrks/chainer,ktnyt/chainer,wkentaro/chainer,chainer/chainer,yanweifu/chainer,truongdq/chainer,kuwa32/chainer,okuta/chainer,kikusu/chainer,benob/chainer,tereka114/chainer,umitanuki/chainer,jnishi/chainer,chainer/chainer,niboshi/chainer,keisuke-umezawa/chainer,elviswf/chainer,tigerneil/chainer,okuta/chainer,t-abe/chainer,t-abe/chainer,ytoyama/yans_chainer_hackathon,kiyukuta/chainer,hvy/chainer,tkerola/chainer,chainer/chainer,niboshi/chainer,ysekky/chainer,benob/chainer,sinhrks/chainer,wkentaro/chainer,wkentaro/chainer,niboshi/chainer,niboshi/chainer,kashif/chainer,wkentaro/chainer,bayerj/chainer,kikusu/chainer,muupan/chainer,cupy/cupy,jfsantos/chainer,AlpacaDB/chainer,jnishi/chainer,cupy/cupy,minhpqn/chainer,okuta/chainer,ikasumi/chainer,cemoody/chainer,Kaisuke5/chainer,wavelets/chainer,jnishi/chainer,rezoo/chainer,woodshop/chainer,cupy/cupy,hvy/chainer,muupan/chainer,keisuke-umezawa/chainer,truongdq/chainer,delta2323/chainer,hvy/chainer,aonotas/chainer,tscohen/chainer,ktnyt/chainer,keisuke-umezawa/chainer,anaruse/chainer,woodshop/complex-chainer,sou81821/chainer,ronekko/chainer,jnishi/chainer,ktnyt/chainer,masia02/chainer,cupy/cupy,laysakura/chainer,pfnet/chainer,hvy/chainer,okuta/chainer,keisuke-umezawa/chainer,hidenori-t/chainer,1986ks/chainer