Colour-code nodes by streetname in Node hunter

When planning routes manually it would be nice if the nodes in the node hunter would have different colours for different streets. That would make it simpler to target the short streets to maximise the completed street count when running in a new city. Just picking a random colour for each street name should be relatively simple to implement instead of using red for all.

Not an issue for my home town where 100% is anyways a goal.