A little correction to Process-File function

Once after processing my C++ source code tree with Process-File my sources became uncompilable. The problem was caused by redirection operator `>', which transformed source files from plain-old ASCII to Unicode. So there's corrected version which uses Out-File cmdlet instead with encoding specified explicitly:

function Process-File([scriptblock]$script, 
                      $filename, 
                      $encoding = "ascii") {
    $local:temp = New-TempFileName
    Get-Content -Encoding $encoding $filename | `
          Foreach $script | `
          out-file -encoding $encoding $local:temp
    Move-Item -force $local:temp $filename
}