message: Use split function from NAS2D
diff: #include <NAS2D/Utility.h>
  #include <NAS2D/Filesystem.h>
  +#include <NAS2D/StringUtils.h>
  #include <NAS2D/Xml/XmlDocument.h>
  #include <NAS2D/Xml/XmlMemoryBuffer.h>
  @@ -455,7 +456,7 @@ void MapViewState::readStructures(Xml::XmlElement* element)
  if (!robotsAttribute->value().empty())
  {
  - for (const auto& string : split_string(robotsAttribute->value().c_str(), ','))
  + for (const auto& string : NAS2D::split(robotsAttribute->value(), ','))
  {
  const int robotId = std::stoi(string);
  for (auto* robot : mRobotPool.robots())
  