Fix update notification service.

fix #721

modoboa/core/utils.py

@@ -25,7 +25,7 @@ def check_for_updates(request):
     }] + extensions
     update_avail = False
     for extension in extensions:
-        if "update" in extension:
+        if extension.get("update"):
             update_avail = True
             break
     return update_avail, extensions

modoboa/lib/api_client.py

@@ -55,7 +55,9 @@ class ModoAPIClient(object):
         from versionfield.version import Version
 
         url = os.path.join(self._api_url, "current_version/")
-        params = {"client_version": self.local_core_version, "site": site}
+        params = {
+            "client_version": self.local_core_version, "client_site": site
+        }
         resp = self.__send_request(url, params)
         if resp is None:
             return None