(PUP-2382) - FFI Puppet feature symlink test
(PUP-2382) - Windows file uses wide_string mixin
fixup with FFI Puppet feature symlink test
(PUP-2382) - Convert Windows MoveFileEx to FFI
(PUP-2382) - Convert ADSI GetComputerName to FFI

  - Add missing error handling for GetComputerName Win32 function
  - Add test that verifies GetComputerName returns a non-empty string