Add missing parentheses

Fixes #25.

src/xdgmenumaker

@@ -396,7 +396,7 @@ def get_entry_info(desktopfile, ico_paths=True):
     # OnlyShowIn but it might be worth using some extra logic here.
     # http://standards.freedesktop.org/menu-spec/latest/apb.html
     if (onlyshowin != [] and not (desktop.lower() in (name.lower() for name in onlyshowin))) \
-        or (desktop.lower() in (name.lower for name in notshowin)) \
+        or (desktop.lower() in (name.lower() for name in notshowin)) \
         or hidden or nodisplay:
         return None