message: Add UI string constants
diff: @@ -204,6 +204,9 @@ namespace constants
  // = UI STRINGS
  // =====================================
  const std::string BUTTON_TAKE_ME_THERE = "Take Me There";
  + const std::string BUTTON_IDLE = "Idle";
  + const std::string BUTTON_ADD_TRUCK = "Add Truck";
  + const std::string BUTTON_REMOVE_TRUCK = "Remove Truck";
  // =====================================
  // = STRUCTURE DISABLED REASONS
  