UI: container: add focus_lost() to allow focus child memorization
UI: window: wrap around once Tab focus leaves window
UI: window: try to find initial focus when showing a window on screen
UI: window: add auto_focus and title properties, remove auto_close
UI: document widget focus movement
UI: provide public access to Widget.move_focus
UI: container: fix move_focus ordering for self vs. children
Merge branch 'window-focus'

* window-focus:
  UI: container: fix move_focus ordering for self vs. children
  UI: provide public access to Widget.move_focus
  UI: document widget focus movement
  UI: window: add auto_focus and title properties, remove auto_close
  UI: window: try to find initial focus when showing a window on screen
  UI: window: wrap around once Tab focus leaves window
  UI: container: add focus_lost() to allow focus child memorization