C65: implement scanline-level VIC-III emulation

[lgblgblgb]

Technically it's still incorrect somewhat, but anyway, the VIC-II timing would be totally different compared to a VIC-III even with a real C65. This project would help to understand the speed impact of this move (which may not affect the real-time emulation of C65, but would affect an M65, so it must be understand better before any M65 work on this depth ...), possible GPU support from SDL from scaling, and other tricks for the M65 related work then!

[lgblgblgb]

The other motivation; it seems even games on the "de-facto" M65 d81 images often uses raster tricks ie to even switch video modes at certain points not mentioning the famous raster bars ... etc. Initially I wouldn't bother with sprites too much and just render them "after" (also the current situation, quite lame: no sprite multiplexing and other tricks, and sprite cannot be "behind the background" either).

[lgblgblgb]

Pull request #34 will hopefully solve this soon :)

[lgblgblgb]