Refactor tree to store locate the SOLPS cells. This is done by changing the 4…

Refactor tree to store the SOLPS cells. This is done by changing the 4 quadrant tree structure to an unstructured binary r-tree. For each addition of a new cell, the node is split based on the smallest area of the resulting nodes heuristic. Since the tree contains the direct cells, this eliminates the need to walk the SOLPS cell when the closes cell was found since this finds the cell a point is in directly. In addition, refactor the r-tree static methods to be instance methods. In total this significantly reduces the code size and reduces the overall run time in half.