Time Travel: Use timestamp in calls to /api/topology

[fbarl]

From #2524:

Clicking on node details makes a direct call to api/topology/[topId]/[nodeId], disregarding the timestamp. So the API needs to be extended similarly to websockets to make the nodes details data consistent with time travel control. The same goes for api/topology? calls which give the info about all the available (sub)topologies as well as their stats (node/edge count, etc...). Here we need to give some thought to the UI, e.g. what happens when the topology we are currently at disappears if we go back in time and it's not currently there?