try {
  $sysDrive = $env:SystemDrive
  $gittfsPath = "$sysDrive\tools\gittfs"
  
  Install-ChocolateyZipPackage 'gittfs' '${DownloadUrl}' $gittfsPath
  Install-ChocolateyPath $gittfsPath

  write-host 'git-tfs has been installed. Call git tfs from the command line to see options. You may need to close and reopen the command shell.'
  Write-ChocolateySuccess 'gittfs'
} catch {
  Write-ChocolateyFailure 'gittfs' $($_.Exception.Message)
  throw 
}

try {
  $sysDrive = $env:SystemDrive
  $gittfsPath = "$sysDrive\tools\gittfs"

  if(test-path $gittfsPath) {
    write-host "Cleaning out the contents of $gittfsPath"
    Remove-Item "$($gittfsPath)\*" -recurse -force
  }
  
  Install-ChocolateyZipPackage 'gittfs' '${DownloadUrl}' $gittfsPath
  Install-ChocolateyPath $gittfsPath

  write-host 'git-tfs has been installed. Call `git tfs` from the command line to see options. You may need to close and reopen the command shell.'
  Write-ChocolateySuccess 'gittfs'
} catch {
  Write-ChocolateyFailure 'gittfs' $($_.Exception.Message)
  throw 
}

Clean the install directory when installing a new version.
Clean the install directory when installing a new version.

h/t @ferventcoder on git-tfs/git-tfs#341
