Merge pull request #123 from Artistan/master

Fix for new curl file upload method.

src/Httpful/Request.php

@@ -382,9 +382,12 @@ public function expectsType($mime)
 
     public function attach($files) {
         foreach ($files as $key => $file) {
-            $this->payload[$key] = "@{$file}";
+            if (function_exists('curl_file_create')) {
+                $this->payload[$key] = curl_file_create($file);
+            } else {
+                $this->payload[$key] = "@{$file}";
+            }
         }
-
         $this->sendsType(Mime::UPLOAD);
         return $this;
     }