ignore _book in watch.js
ignore _book in watch.js

npracht/documentation,CN-Sean/gitbook,iflyup/gitbook,iamchenxin/gitbook,CN-Sean/gitbook,nycitt/gitbook,mautic/documentation,megumiteam/documentation,athiruban/gitbook,rohan07/gitbook,iflyup/gitbook,haamop/documentation,iamchenxin/gitbook,boyXiong/gitbook,ryanswanson/gitbook,guiquanz/gitbook,gaearon/gitbook,minghe/gitbook,tzq668766/gitbook,tzq668766/gitbook,gdbooks/gitbook,webwlsong/gitbook,megumiteam/documentation,xcv58/gitbook,sunlianghua/gitbook,tshoper/gitbook,guiquanz/gitbook,youprofit/gitbook,sudobashme/gitbook,sunlianghua/gitbook,minghe/gitbook,FKV587/gitbook,alex-dixon/gitbook,rohan07/gitbook,wewelove/gitbook,tshoper/gitbook,athiruban/gitbook,youprofit/gitbook,wewelove/gitbook,gaearon/gitbook,mautic/documentation,qingying5810/gitbook,xcv58/gitbook,nycitt/gitbook,FKV587/gitbook,grokcoder/gitbook,gdbooks/gitbook,gencer/gitbook,npracht/documentation,escopecz/documentation,GitbookIO/gitbook,alex-dixon/gitbook,boyXiong/gitbook,qingying5810/gitbook,haamop/documentation,thelastmile/gitbook,grokcoder/gitbook,thelastmile/gitbook,gencer/gitbook,webwlsong/gitbook,shibe97/gitbook,strawluffy/gitbook,shibe97/gitbook,escopecz/documentation,sudobashme/gitbook