Choice button does not work well

- Rename classes and methods
  - Use Factory for classes that have methods to create class instances
  - Use Formatter for classes that have a format method that produces
    a text representation of a widget for a UI file. This distinguishes
    from Device Widgets that determine the widget that will be created
    for a Signal.
  - Class renames:
    - WidgetTemplate -> UITemplate
    - WidgetFactory -> WidgetFormatter
    - GroupFactory -> GroupWidgetFormatter
    - LayoutProperties -> ScreenLayout
    - ScreenWidgets -> WidgetFormatterFactory
    - Screen -> ScreenFormatterFactory
  - Screen method renames:
    - screen -> create_screen_formatter
    - create_sub_screens -> create_sub_screen_formatters
    - component -> generate_component_formatters
    - make_group_widget -> create_group_formatters
    - group -> create_group_formatter
    - make_component_widgets -> create_component_widget_formatters
- Make passing of ui properties to formatter more explicit and pass
  widget to formatter as a parameter separate to the properties map
- Expand one character variables
- mypy fixes
- Update docs ref

Add 3.10 to setup.cfg, as it is tested.