api_key_authentication.go
func apiKeyAuth(key string, secret string) *apiKeyAuthentication {
	a := apiKeyAuthentication{
		Key:     key,
		Secret:  secret,
		BaseUrl: config.BaseUrl,
		Client: http.Client{
			Transport: &http.Transport{
				Dial: dialTimeout,
			},
		},
	}
	return &a
}
func apiKeyAuth(key string, secret string) *apiKeyAuthentication {
	a := apiKeyAuthentication{
		Key:     key,
		Secret:  secret,
		BaseUrl: config.BaseUrl,
		Client: http.Client{
			Transport: &http.Transport{
				Dial: dialTimeout,
			},
		},
	}
	return &a
}
// ApiKeyAuth instantiates ApiKeyAuthentication with the API key & secret