Have importprivkey use CWallet's ImportPrivKeys, ImportScripts, and ImportScriptPubKeys
Have importprivkey use CWallet's ImportPrivKeys, ImportScripts, and ImportScriptPubKeys

Behavior changes:
* If we already have the key, it's wpkh script will still be added, although it should already be there


Former-commit-id: 1888311029fbf959ee619d459ad8b955d9c5a2d5
syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin