Suggest: give a warning for reuse LupinusHTTP

[azu]

LupinusHTTPRequest *httpRequest = [self.lupinusHTTP request:LupinusMethodGET URL:endPoint];
[httpRequest responseJSON:^(NSURLRequest *request, NSURLResponse *response, id JSON, NSError *error) {

}];

// finish request 
// reuse lupinusHTTP should be error!
LupinusHTTPRequest *reuseHttpRequest = [self.lupinusHTTP request:LupinusMethodGET URL:endPoint];