Web UI doesn't reuse inflight template requests

[strugee]

STR:

1. Go to a user's page
2. Open the devtools Network pane
3. Scroll all the way to the bottom
4. Note how there's a ton of requests for activity-client.jade.js

This is incredibly inefficient. We need to detect that these requests are already in-flight and reuse the existing request.

[ghost]

I thinks is related with this: pump.js#L497 and view.js#L225, because when the user scroll down fire, scroll more and fire again, and if the request is slow the user will be scroll up and down again, makes the request again.

I think exist better option than setInterval for that, but also should be detect if exist similar request for template

[ghost]

The commit 92e9f05 will fix this issue.

But the infinite scroll has other impact in performance with current behavior (better with $(window).on('scroll'..)), but is other issue