Update README.md

Author: ahaenggli

README.md

@@ -4,7 +4,15 @@ Im Verzeichnis werden sämtliche sichtbaren Register aufgeführt und sind direkt
 Die Standard-Einstellungen lassen sich via F5 > Button "config" einsehen und editieren.
 
 ## Wie installiere ich ein Excel-Add-In?
-https://support.office.com/de-de/article/add-or-remove-add-in-in-excel-0af570c4-5cf3-4fa9-9b88-403625a0b460
+PowerShell: 
+```PowerShell
+Invoke-WebRequest "https://github.com/ahaenggli/Excel-PlugIn-TableOfContents/releases/latest/download/TableOfContentsWorksheetGenerator.xlam" -OutFile $env:APPDATA"\Microsoft\AddIns\TableOfContentsWorksheetGenerator.xlam"
+$xl=New-Object -ComObject excel.application
+$xl.Application.AddIns | ?{$_.Name -eq 'TableOfContentsWorksheetGenerator.xlam'} | %{$_.Installed=$true}
+$xl.Quit()
+```
+Manuell in Excel:  
+https://support.office.com/de-de/article/add-or-remove-add-in-in-excel-0af570c4-5cf3-4fa9-9b88-403625a0b460  
 
 ## Wie kann ich das Inhaltsverzeichnis erstellen?
 Einfach die F5-Taste anklicken.
@@ -31,6 +39,14 @@ Optionally, further attributes such as description, date of creation, status, an
 The default settings can be viewed and edited via F5 > "config"-button.
 
 ## How to install an Excel add-in
+PowerShell: 
+```PowerShell
+Invoke-WebRequest "https://github.com/ahaenggli/Excel-PlugIn-TableOfContents/releases/latest/download/TableOfContentsWorksheetGenerator.xlam" -OutFile $env:APPDATA"\Microsoft\AddIns\TableOfContentsWorksheetGenerator.xlam"
+$xl=New-Object -ComObject excel.application
+$xl.Application.AddIns | ?{$_.Name -eq 'TableOfContentsWorksheetGenerator.xlam'} | %{$_.Installed=$true}
+$xl.Quit()
+```
+Excel:  
 https://support.office.com/en-us/article/add-or-remove-add-ins-in-excel-0af570c4-5cf3-4fa9-9b88-403625a0b460
 
 ## How can I generate the table of contents worksheet?
@@ -50,4 +66,4 @@ Sure, just click F5 and use the config button to customize it.
 The name of the index sheet, wich properties are available on each sheet, which properties you want in the index sheet and of course their order.
 
 ## I used F5 for the Excel's GoTo
-You can use [CTRL]+G instead.
+You can use [CTRL]+G instead.