msg on mining key

src/simplewallet/simplewallet.cpp

@@ -766,7 +766,7 @@ bool simple_wallet::spendkey(const std::vector<std::string> &args/* = std::vecto
     std::cout << "secret: On device. Not available" << std::endl;
   } else {
     SCOPED_WALLET_UNLOCK();
-    printf("secret: ");
+    printf("secret (key used for mining): ");
     print_secret_key(m_wallet->get_account().get_keys().m_spend_secret_key);
     putchar('\n');
   }