Add 'task_RotaryEncoder' detection for additional cameras.
S100 update from rudi:
http://chdk.setepontos.com/index.php?topic=650.msg102697#msg102697
SX240 update from nafraf:
http://chdk.setepontos.com/index.php?topic=650.msg102699#msg102699
Fix OSD bug from nafraf:
http://chdk.setepontos.com/index.php?topic=650.msg102738#msg102738