Replace the use of hanko with public keys.

src/main.cpp

@@ -37,7 +37,7 @@ void printHelp()
 	cout << "     stop" << endl;
 	cout << "     tx" << endl;
 	cout << "     unl_add <public> [<comment>]" << endl;
-	cout << "     unl_delete <hanko>" << endl;
+	cout << "     unl_delete <public_key>" << endl;
 	cout << "     unl_list" << endl;
 	cout << "     unl_reset" << endl;
 	cout << "     unlock <passphrase>" << endl;