Feature: Implement posix-find command with powershell

[chen3feng]

gci -r | where { $_.Length -gt ( 3 * 1024 ) -or $_.LastWriteTime -gt "04/23/2020" }  | Select FullName

See:

• https://jessitron.com/2020/04/23/powershell-equivalent-of-find/
• https://stackoverflow.com/questions/2157554/how-to-handle-command-line-arguments-in-powershell
• https://en.wikipedia.org/wiki/Forfiles