#199 Record post-processed video

[Maarten ter Huurne]

When recording a video, we apply the most simple scaling possible to generate a 320x240 or 640x480 video. It would be useful to also allow recording of post processed frames (including scaler, scanlines etc) and allow recording of the output including the OSD layer (for instruction videos on YouTube, for example).

For screenshots we already have the option to capture only the MSX screen or the full openMSX output.