Performance improvement for get_raw_pixel & set_raw_pixel from lapser.
http://chdk.setepontos.com/index.php?topic=8932.msg96567#msg96567
Update to raw_init_badpixel_bin for clarity and a small performance improvement.
Sig finder update to find viewport_buffers and active_viewport_buffer for DryOS versions R43, R45, R47, R49, & R50.