* [doc] fixed return type of some virtual-DOM APIs
* [doc] fixed return type of some virtual-DOM APIs

lvscar/weex,Hanks10100/incubator-weex,acton393/incubator-weex,KalicyZhou/incubator-weex,namedlock/weex,dianwodaMobile/DWeex,bigconvience/weex,weexteam/incubator-weex,acton393/incubator-weex,leoward/incubator-weex,misakuo/incubator-weex,Tancy/weex,dianwodaMobile/DWeex,namedlock/weex,zhangquan/weex,boboning/weex,yuguitao/incubator-weex,alibaba/weex,acton393/weex,alibaba/weex,MrRaindrop/weex,MrRaindrop/weex,acton393/weex,miomin/incubator-weex,misakuo/incubator-weex,acton393/weex,erha19/incubator-weex,LeeJay0226/weex,zhangquan/weex,namedlock/weex,acton393/incubator-weex,xiayun200825/weex,lvscar/weex,dianwodaMobile/DWeex,acton393/incubator-weex,KalicyZhou/incubator-weex,weexteam/incubator-weex,miomin/incubator-weex,Neeeo/incubator-weex,MrRaindrop/weex,kfeagle/weex,alibaba/weex,KalicyZhou/incubator-weex,HomHomLin/weex,MrRaindrop/weex,MrRaindrop/weex,alibaba/weex,misakuo/incubator-weex,LeeJay0226/weex,Tancy/weex,lvscar/weex,Tancy/weex,Hanks10100/weex,MrRaindrop/incubator-weex,bigconvience/weex,xiayun200825/weex,MrRaindrop/incubator-weex,Hanks10100/incubator-weex,kfeagle/weex,alibaba/weex,Hanks10100/incubator-weex,zzyhappyzzy/weex,miomin/incubator-weex,cxfeng1/weex,erha19/incubator-weex,yuguitao/incubator-weex,misakuo/incubator-weex,namedlock/weex,yuguitao/incubator-weex,erha19/incubator-weex,acton393/weex,kfeagle/weex,Neeeo/incubator-weex,leoward/incubator-weex,lvscar/weex,erha19/incubator-weex,lvscar/weex,xiayun200825/weex,acton393/incubator-weex,xiayun200825/weex,cxfeng1/weex,erha19/incubator-weex,xiayun200825/weex,LeeJay0226/weex,boboning/weex,miomin/incubator-weex,KalicyZhou/incubator-weex,boboning/weex,erha19/incubator-weex,cxfeng1/weex,erha19/incubator-weex,LeeJay0226/weex,misakuo/incubator-weex,miomin/incubator-weex,misakuo/incubator-weex,erha19/incubator-weex,dianwodaMobile/DWeex,cxfeng1/weex,KalicyZhou/incubator-weex,zhangquan/weex,boboning/weex,zzyhappyzzy/weex,zzyhappyzzy/weex,namedlock/weex,Neeeo/incubator-weex,HomHomLin/weex,zhangquan/weex,weexteam/incubator-weex,miomin/incubator-weex,bigconvience/weex,yuguitao/incubator-weex,zzyhappyzzy/weex,acton393/weex,HomHomLin/weex,boboning/weex,Neeeo/incubator-weex,miomin/incubator-weex,Tancy/weex,weexteam/incubator-weex,cxfeng1/incubator-weex,Hanks10100/incubator-weex,Hanks10100/incubator-weex,weexteam/incubator-weex,acton393/incubator-weex,LeeJay0226/weex,Tancy/weex,Hanks10100/weex,dianwodaMobile/DWeex,cxfeng1/incubator-weex,alibaba/weex,Hanks10100/weex,leoward/incubator-weex,Neeeo/incubator-weex,leoward/incubator-weex,dianwodaMobile/DWeex,Hanks10100/weex,zhangquan/weex,Hanks10100/weex,MrRaindrop/incubator-weex,MrRaindrop/incubator-weex,Hanks10100/incubator-weex,kfeagle/weex,zzyhappyzzy/weex,namedlock/weex,bigconvience/weex,LeeJay0226/weex,zzyhappyzzy/weex,cxfeng1/weex,cxfeng1/incubator-weex,leoward/incubator-weex,zhangquan/weex,acton393/incubator-weex,Tancy/weex,HomHomLin/weex,bigconvience/weex,cxfeng1/incubator-weex,leoward/incubator-weex,KalicyZhou/incubator-weex,kfeagle/weex,Hanks10100/incubator-weex,cxfeng1/incubator-weex,HomHomLin/weex,alibaba/weex,MrRaindrop/incubator-weex,bigconvience/weex,Hanks10100/weex,MrRaindrop/incubator-weex,Neeeo/incubator-weex,xiayun200825/weex,boboning/weex,miomin/incubator-weex,cxfeng1/weex,MrRaindrop/weex,cxfeng1/incubator-weex,Hanks10100/incubator-weex,kfeagle/weex,yuguitao/incubator-weex,acton393/incubator-weex,yuguitao/incubator-weex,HomHomLin/weex,lvscar/weex,weexteam/incubator-weex,acton393/weex