tweak readme
tweak readme

xiuzhifu/ffjson,sunminghong/ffjson,xiuzhifu/ffjson,pquerna/ffjson,xladykiller/ffjson,jamesliu96/ffjson,pquerna/ffjson,xyliuke/ffjson,cw2018/ffjson,xyliuke/ffjson,cmeon/ffjson,cmeon/ffjson,trigrass2/ffjson,sunminghong/ffjson,trigrass2/ffjson,jamesliu96/ffjson,cw2018/ffjson,xladykiller/ffjson