message: Load UI overla font from asset path
  Refs
diff: +
  /*
  * UI overlay class using ImGui
  *
  @@ -72,7 +73,8 @@ namespace vks
  delete[] fontAsset;
  }
  #else
  - io.Fonts->AddFontFromFileTTF("./../data/Roboto-Medium.ttf", 16.0f);
  + const std::string filename = getAssetPath() + "Roboto-Medium.ttf";
  + io.Fonts->AddFontFromFileTTF(filename.c_str(), 16.0f);
  #endif
  io.Fonts->GetTexDataAsRGBA32(&fontData, &texWidth, &texHeight);
  VkDeviceSize uploadSize = texWidth*texHeight * 4 * sizeof(char);
  