message: Qt 5.6 is our minspec, don't use functions added since then
diff: @@ -327,7 +327,7 @@ public:
  {
  if(node->file.lastmod == 0)
  return QVariant();
  - return QDateTime::fromSecsSinceEpoch(node->file.lastmod);
  + return QDateTime(QDate(1970, 1, 1), QTime(0, 0, 0), Qt::UTC).addSecs(node->file.lastmod);
  }
  default: break;
  }
  