Merge pull request #219 from qibinghua/master

CURLOPT_HTTPHEADER在php7接受空数组导致php-fpm奔溃

Author: rmccue

library/Requests/Transport/cURL.php

@@ -375,8 +375,9 @@ protected function setup_handle($url, $headers, $data, $options) {
 		curl_setopt($this->handle, CURLOPT_URL, $url);
 		curl_setopt($this->handle, CURLOPT_REFERER, $url);
 		curl_setopt($this->handle, CURLOPT_USERAGENT, $options['useragent']);
-		curl_setopt($this->handle, CURLOPT_HTTPHEADER, $headers);
-
+		if (!empty($headers)) {
+			curl_setopt($this->handle, CURLOPT_HTTPHEADER, $headers);
+		}
 		if ($options['protocol_version'] === 1.1) {
 			curl_setopt($this->handle, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
 		}