changes needed for migrating show creation from Windows to Linux

As noted in an earlier post, 

https://hnsws.blogspot.com/2020/01/warping-on-linux-filter-on-avisynth-and.html

avisynth works on Linux under Wine, with certain changes.

• need to run Virtualdub with
  cd ~/windows/VirtualDub
  wine VirtualDub
• need to add the line 
  Loadplugin("/home/myusername/.wine/drive_c/Program Files/AviSynth 2.5/plugins/ffms2.dll")
• need to use FFvideosource("in.mp4") instead of DirectShowSource()

The wav to 5.1 AC3 is done well by ffmpeg,
https://hnsws.blogspot.com/2020/01/6-mono-waves-to-51-ac3-using-ffmpeg.html