Update readme.txt

Author: jamesmontemagno

nuget/readme.txt

@@ -2,6 +2,12 @@ Settings Plugin Readme
 
 See more at: https://github.com/jamesmontemagno/SettingsPlugin/blob/master/CHANGELOG.md
 
+## News
+- Plugins have moved to .NET Standard and have some important changes! Please read my blog:
+http://motzcod.es/post/162402194007/plugins-for-xamarin-go-dotnet-standard
+
+-New changes in Settings API: GetValueOrDefault and AddOrUpdateValue are no longer generic and you must pass in only supported types.
+
 ### Important
 Ensure that you install NuGet into ALL projects.