message: Remove if check for empty string
  The string split on an empty string will return an empty vector, so the
  range for loop code will naturally skip over the contents anyway.
diff: @@ -454,8 +454,6 @@ void MapViewState::readStructures(Xml::XmlElement* element)
  auto& rcc = *static_cast<RobotCommand*>(&structure);
  XmlAttribute* robotsAttribute = structureNode->firstChildElement("robots")->firstAttribute();
  - if (!robotsAttribute->value().empty())
  - {
  for (const auto& string : NAS2D::split(robotsAttribute->value(), ','))
  {
  const auto robotId = NAS2D::stringTo<int>(string);
  @@ -469,7 +467,6 @@ void MapViewState::readStructures(Xml::XmlElement* element)
  }
  }
  }
  - }
  structure.populationAvailable()[0] = pop0;
  structure.populationAvailable()[1] = pop1;
  