Setup vapoursynth for mpv

1. Get latest Vapoursynth with same type (32/64-bit) as mpv. Download portable version and extract it in same folder as mpv.exe.

2. Get latest Python. Download the embeddable file and extract it in same folder as mpv.exe. Always double check python's version requirement for vapoursynth.

3. Download additional vapoursynth plugins like mvtools. Extract the library and copy into vapoursynth64\plugins folder.

4. You may need additional plugins, depends on what the vapoursynth script do

Vapoursynth script example:

# https://www.l33tmeatwad.com/vapoursynth101/script-basics
# example.vpy

import vapoursynth as vs
from vapoursynth import core
video = core.std.BlankClip(width=640,height=480, format=vs.RGB24, length=500, fpsnum=2997, fpsden=125, color=[0, 0, 0])
video.set_output()