message: importprivkey -> importwallet recommendation
  Change recommended command from `importprivkey` (which only imports individual private keys) to `importwallet` (which imports the whole wallet).
diff: <item>
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  - <string>We have detected that your wallet does not use a HD seed. A HD seed allows you to restore all your private keys and also Sigma mints even when restoring from an old backup.
  + <string>We have detected that your wallet does not use an HD seed. An HD seed allows you to restore all your private keys and also Sigma mints when restoring from a backup.
  -To have Sigma private transactions functionality, a HD wallet is required. We highly recommend that you create a new wallet and move your funds over to the new wallet version or use the dumpwallet in conjunction with importprivkey commands to move the keys to the new wallet.
  +To have Sigma private transactions functionality, an HD wallet is required. We highly recommend that you create a new wallet and send your funds over to the newly-created wallet or use the <tt>dumpwallet</tt> command in conjunction with <tt>importwallet</tt> to move your keys to the new wallet.
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  <property name="alignment">
  