[dashboard] reduce resource consumption?

[schloett]

The dashboard is quite heavyweight, maybe it would be possible to reduce resource consumption by doing calculations for visualizations on demand? (Might be the case already, I'm not into the code. From the outside it looks like uRank for example does all the computation, even if the timeline is shown).
Also the use of webworkers might be an option (The loading animation seems to freeze when opening the landscape vis)