Add "Custom" option to Auto Setup

scripts/auto_setup.py

@@ -83,6 +83,7 @@ PRESETS = {
       'Partitions 4K Aligned',
       ),
     },
+  'Custom': {}, # Will remain empty at runtime
   }
 
 # Classes

scripts/wk/setup/win.py

@@ -311,6 +311,7 @@ def build_menus(base_menus, title, presets):
   MENU_PRESETS.add_option('Default')
   for name in presets:
     MENU_PRESETS.add_option(name)
+  MENU_PRESETS.add_option('Custom')
   MENU_PRESETS.add_action('Main Menu')
   MENU_PRESETS.add_action('Quit')
   MENU_PRESETS.update()