Switch StaticRTree leaf size to 256 elements per leaf

This increses query performance dramatically for queries with a lot of
coordinates. However it increases the internal memory usage of the
StaticRTree also 4x.

include/util/static_rtree.hpp

@@ -42,7 +42,7 @@ template <class EdgeDataT,
           class CoordinateListT = std::vector<Coordinate>,
           bool UseSharedMemory = false,
           std::uint32_t BRANCHING_FACTOR = 64,
-          std::uint32_t LEAF_NODE_SIZE = 1024>
+          std::uint32_t LEAF_NODE_SIZE = 256>
 class StaticRTree
 {
   public: