db/GroupManager: early return, no functional changes

src/node/db/GroupManager.js

@@ -62,13 +62,12 @@ exports.deleteGroup = function(groupID, callback)
         if(_group == null)
         {
           callback(new customError("groupID does not exist","apierror"));
+          return;
         }
+
         //group exists, everything is fine
-        else
-        {
         group = _group;
         callback();
-        }
       });
     },
     //iterate trough all pads of this groups and delete them