Price Nodes Refactor Suggestion

[bradenpecora]

I've always believed that the price nodes system isn't great for determining prices and I think I've thought of an approach that I'm optimistic about:

• (Remove price nodes)
• Solve for capacity at a fixed price
• If all capacity is met, decrease price at that node (decrease by a slightly random amount)
• If capacity is not met, increase price (some randomness)
• Solve again and repeat until changes in capacity are minimal or objective is maximized