Fix JSON decode error (#57)

Author: paulineribeyre

indexclient/client.py

@@ -28,7 +28,7 @@ def handle_error(resp):
         try:
             json = resp.json()
             resp.reason = json["error"]
-        except KeyError:
+        except (json.decoder.JSONDecodeError, KeyError):
             pass
         finally:
             resp.raise_for_status()