Non-backwards compatible changes in camera specific code

CHDK 1.2

https://trac.assembla.com/chdk/changeset/2483

• state_kbd_script_run is now part of a structure

Firmware variables

canon_shoot_menu_active

becomes nonzero (observed value: 1) when the camera is in record mode and either of the following conditions is true

• shooting menu is shown (the one you activate with the func/set button)
• AEL (exposure lock) or AFL (AF lock) is active
• maybe when other similar Canon function is active (for example FE lock)

Default CHDK action (as of r1997): OSD will vanish when this becomes nonzero. If this is undesired, CAM_SHOW_OSD_IN_SHOOT_MENU needs to be defined in the camera's platform_camera.h.