add docs for DQuery
add docs for DQuery

windreamer/dpark,yhj630520/dpark,windreamer/dpark,zzl0/dpark,zzl0/dpark,windreamer/dpark,quxiaolong1504/dpark,fe11x/dpark,douban/dpark,dogeyes/dpark,dogeyes/dpark,fe11x/dpark,daishaowei/dpark,oceanjack/dpark,douban/dpark,junmoa/dpark,smarthomekit/dpark,quxiaolong1504/dpark,ee08b397/dpark,oceanjack/dpark,douban/dpark,veritynoob/dpark,mageia/dpark,daishaowei/dpark,mageia/dpark,junmoa/dpark,veritynoob/dpark,Mignet/dpark,yhj630520/dpark,304471720/dpark,veritynoob/dpark,smarthomekit/dpark,douban/dpark,windreamer/dpark,smarthomekit/dpark,douban/dpark,yhj630520/dpark,yanheven/dpark,Mignet/dpark,dogeyes/dpark,yanheven/dpark,304471720/dpark,304471720/dpark