What is the intention of the groups feature? It seems like a really powerful way to group stuff together and have interesting views of things. But right now it just generates a list of entities that you can click through or hover over. I took a look at the code that generates all the various graph layouts (iftypes, health, ports). It seems that every page has its own code for handling the graph layout. It seem like this would be a great place to leverage a bunch of the existing code so you can create group specific views of sensors, ports etc... But it doesn't look like the code is structured that way (i.e reusable components/widgets).