code: public SecretResponse createSecret(String apiKey, String secret) throws IOException, NexmoClientException {
          return createSecret(new CreateSecretRequest(apiKey, secret));
      }
docs: Create a secret to be used with a specific API key.
  
  @param apiKey The API key that the secret is to be used with.
  @param secret The contents of the secret.
  
  @return SecretResponse object which contains the created secret from the API.
  
  @throws IOException          if a network error occurred contacting the Nexmo Account API
  @throws NexmoClientException if there was a problem wit hthe Nexmo request or response object indicating that the request was unsuccessful.