Fixed node size scaling with tech restrictions

When not all of the potential scales have been unlocked in the tech tree
incorrect node sizes were being selected for use.

This seems to fix the problem, however I didn't look deeply enough to fully understand the maths this line is doing, so please double check the change makes sense.
You're right that this code is wrong. Sadly, so is yours. ):

The correct code here would be:

    node.size = (int)(baseNode.size + (Tools.ClosestIndex(tweakScale, config.allScaleFactors) - Tools.ClosestIndex(defaultScale, config.allScaleFactors)) / (float)config.allScaleFactors.Length * 5);

Your solution would give the same node size to 1.25m and 3.75m in these cases respectively:

1.25m: 62.5cm, 1.25m, 5m unlocked.
3.75m: 62.5cm, 3.75m, 5m unlocked.

So if you update to the code above, I'll merge this.