How long can I see the updated document in website After merge the PR

[chengduoZH]

How long can I see the updated document In this web site when I modify code document and merge it.

[pkuyym]

I have updated the equation for huber loss op, but the html page doesn't display normally.

[luotao1]

@jetfuel Can you answer "How long can I see the updated document in website" in #6014?

[jetfuel]

@luotao1 Once the the #6014 is merged, you should be able to see updated content in about 25 minutes. Travis CI will update the contents.