Update mkdocs.yml
Update mkdocs.yml

add a resource page for published video and talks
wzhongyuan/BigDL,luchy0120/BigDL,qiuxin2012/BigDL,zhangxiaoli73/BigDL,luchy0120/BigDL,i8run/BigDL-1,wzhongyuan/BigDL,qiuxin2012/BigDL,wzhongyuan/BigDL,i8run/BigDL-1,yiheng/BigDL,i8run/BigDL-1,luchy0120/BigDL,zhangxiaoli73/BigDL,yiheng/BigDL,jenniew/BigDL,jenniew/BigDL,jenniew/BigDL,zhangxiaoli73/BigDL,qiuxin2012/BigDL,yiheng/BigDL