Implement head method

Author: baptistejamin

restclient.php

@@ -120,6 +120,10 @@ public function delete($url, $parameters=[], $headers=[]){
         return $this->execute($url, 'DELETE', $parameters, $headers);
     }
 
+    public function head($url, $parameters=[], $headers=[]){
+        return $this->execute($url, 'HEAD', $parameters, $headers);
+    }
+    
     public function execute($url, $method='GET', $parameters=[], $headers=[]){
         $client = clone $this;
         $client->url = $url;