[SmartSkip] On windows, powershell [Get-FileHash] can take up to 1x seconds on the first run

[Mark-Joy]

Hello,
As title, please don't use powershell since this tool can take a long time (up to 1x seconds) on the first run (after restart/# computer). My processor is Intel i3-6100.
And it take an average of 300-ms on subsequent runs (not a problem after the first run).

To reproduce the issue:

• Restart computer. Wait for it to complete boot up.
• Open any video file.

Here are 2 examples:

Consider to use pure-lua-hash instead. It takes only 1-ms to complete not only MD5 but also sha256. And you don't have to run subprocess command.
Here is the commit: 1fccdb5 that use pure_lua_SHA
You can also choose SHA256 instead of MD5.

[Eisa01]

I really like it, however, loading and downloading additional scripts might be a problem for some of the non-tech users. Sadly, there is no way around it :/