Added extra feature install

Author: sanderstad

tests/appveyor/preparation.ps1

@@ -24,6 +24,7 @@ Install-Module -Name PSFramework | Out-Null
 # Get Hyper-V-PowerShell
 Write-Host -Object "appveyor.prep: Install Hyper-V-PowerShell" -ForegroundColor DarkGreen
 Install-WindowsFeature -Name Hyper-V-PowerShell | Out-Null
+Install-WindowsFeature RSAT-Hyper-V-Tools -IncludeAllSubFeature | Out-Null
 
 # Creating config files
 Write-Host -Object "appveyor.prep: Creating configurations files" -ForegroundColor DarkGreen