Change the values of QDirModel::FileNameRole and QDirModel::FilePathRole to be less than Qt::UserRole

The documentation states that Qt::UserRole (32) is "The first role that can be used for application-specific purposes". This implies that all roles after this value are also reserved for user applications. However, this is not true if the user is using QDirModel because it uses two enumeration values that are currently inside this reserved range; QDirModel::FilePathRole and QDirModel::FileNameRole. If possible, these two should have their values changed to something less than 32.