Also consider NuGet.org for Umbraco.Cms.* packages

Author: ronaldbarendse

NuGet.config

@@ -9,6 +9,7 @@
   <packageSourceMapping>
     <packageSource key="nuget.org">
       <package pattern="*" />
+      <package pattern="Umbraco.Cms.*" />
     </packageSource>
     <packageSource key="Umbraco Prereleases">
       <package pattern="Umbraco.Cms.*" />