update readme

README.md

@@ -8,6 +8,9 @@ At the moment it's far away from being complete or even good. Right now it as so
 Install the latest version of `Pilz.Dalamud` via NuGet Package Manager or NuGet Console:\
 https://www.nuget.org/packages/Pilz.Dalamud
 
+Or add the alternative package source for slightly quicker updates:\
+`<add key="Pilz.Dalamud" value="https://git.pilzinsel64.de/api/v4/projects/8/packages/nuget/index.json" />`\
+
 ## Get started
 
 ### Initialize Plugin Services