Update NUGET sources

Author: mattbrailsford

NuGet.config

@@ -3,28 +3,5 @@
   <packageSources>
     <clear />
     <add key="nuget.org" value="https://api.nuget.org/v3/index.json" />
-    <add key="Umbraco Prereleases" value="https://www.myget.org/F/umbracoprereleases/api/v3/index.json" />
-    <add key="Umbraco Nightly" value="https://www.myget.org/F/umbraconightly/api/v3/index.json" />
-    <add key="Umbraco Cloud Bundle" value="https://www.myget.org/F/uc-bundle/api/v3/index.json" />
   </packageSources>
-  <packageSourceMapping>
-    <packageSource key="nuget.org">
-      <package pattern="*" />
-      <package pattern="Umbraco" />
-      <package pattern="Umbraco.*" />
-    </packageSource>
-    <packageSource key="Umbraco Cloud Bundle">
-      <package pattern="Umbraco.*" />
-    </packageSource>
-    <packageSource key="Umbraco Prereleases">
-      <package pattern="Umbraco.Commerce" />
-      <package pattern="Umbraco.Commerce.*" />
-      <package pattern="Umbraco.Licenses" />
-    </packageSource>
-    <packageSource key="Umbraco Nightly">
-      <package pattern="Umbraco.Commerce" />
-      <package pattern="Umbraco.Commerce.*" />
-      <package pattern="Umbraco.Licenses" />
-    </packageSource>
-  </packageSourceMapping>
 </configuration>