message: Update check for Unset cacheIndex
diff: @@ -604,7 +604,7 @@ void MicroPather::GetNodeNeighbors(PathNode* node, std::vector< NodeCost >* pNod
  // it has no neighbors.
  pNodeCost->resize(0);
  }
  - else if (node->cacheIndex < 0)
  + else if (node->cacheIndex == Unset)
  {
  // Not in the cache. Either the first time or just didn't fit. We don't know
  // the number of neighbors and need to call back to the client.
  