message: don't report minversion wallet entry as unknown
diff: @@ -509,7 +509,8 @@ ReadKeyValue(CWallet* pwallet, CDataStream& ssKey, CDataStream& ssValue,
  strErr = "Error reading wallet database: Unknown non-tolerable wallet flags found";
  return false;
  }
  - } else if (strType != "bestblock" && strType != "bestblock_nomerkle") {
  + } else if (strType != "bestblock" && strType != "bestblock_nomerkle" &&
  + strType != "minversion") {
  wss.m_unknown_records++;
  }
  } catch (...)
  