TODOs:
- convert into HTML
- maybe display inside a R77 specific help dialog (from Command dialog)
- check if Command dialog and Settings shoud use the same button (16:9,4:3)
- explain Command and Settings dialog
- explain Power-on options dialog (or refer to Stella User's Guide)

*** Navigation ***

Stella can be controlled via the console buttons or a joystick in left or
right port.

Inside Launcher:
  Joystick   Button      Action
  ----------------------------------------------------
  Up         SAVE        previous game
  Down       RESET       next game
  Left       LOAD        page up
  Right      MODE        page down
  Button 1   SKILL P1    start selected game
  Button 2   SKILL P2    open Power-on options dialog
  Button 4   COLOR,B/W   open Settings dialog

Inside a dialog:
  Joystick   Button      Action
  -----------------------------------------------------
  Up         SAVE        change/increase current option
  Down       RESET       change/decrease current option
  Left       LOAD        previous dialog element
  Right      MODE        next dialog element
  Button 1   SKILL P1    select
  Button 2   SKILL P2    cancel
  Button 3   4:3,16:9    previous tab
  Button 4   FRY         next tab

During emulation:
  The joysticks work normal and all console buttons as labeled except of the
  following.

  Joystick  īButton      Action
  ----------------------------------------------
  Button 3   4:3,16:9    open the Command dialog
  Button 4   -           open Settings dialog
  Button 5   FRY         return to Launcher

Note: If you have a keyboard attached via OTG all keys work as described in
the Stella User's Guide.