Propose "tasks" view of dashboard to not be streaming

This came up when speaking with @rabernat today which is a problem I've experimenced too. When going to "tasks" view the expectation is to see the history of all the tasks you've done. But the tasks view is streaming.

So I briefly see a flash of the, say, 100k tasks that have gone before then they all disappear as new tasks come in.

We should have a view where we can see all tasks, even if computation is ongoing. The simple way to do this would be to make tasks not streaming. With the main status page being the streaming view.