Fix performence in dashboard

[haaavk]

Fix #261

[milesmcc]

Looks good; I need to test more robustly but I think it's on the right track. Would you mind posting some screenshots on the PR?

[haaavk]

I used sessions list template as starter.

shynet1.mp4

[milesmcc]

Hmm, the video isn't working for me but it might be my computer.

I apologize for my slowness here. The underlying issue is that I got a new laptop, and I no longer have a good local development environment for Shynet where I can easily pull your changes and test them out. (And alas, we don't have a way to seed mock data.) This is my fault.

[haaavk]

Maybe this will work.

shynet.mov

I had the same problem with mock data but I found management command call "demo". I made some cosmetic changes to it but it mostly works really good out of the box.

[milesmcc]

Good work.