Refreshes the path variable in a Powershell session. Taken from http://stackoverflow.com/questions/14381650/how-to-update-windows-powershell-session-environment-variables-from-registry

Refresh-Path.ps1

foreach($level in "Machine","User") {
   [Environment]::GetEnvironmentVariables($level).GetEnumerator() | % {
      # For Path variables, append the new values, if they're not already in there
      if($_.Name -match 'Path$') { 
         $_.Value = ($((Get-Content "Env:$($_.Name)") + ";$($_.Value)") -split ';' | Select -unique) -join ';'
      }
      $_
   } | Set-Content -Path { "Env:$($_.Name)" }
}

Thanks. This helped me resolve an issue where I have to install an MSI inside an AppVeyor build and therefore had to refresh the path.