Add nuget config to solution folder

nuget.config

@@ -1,6 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <configuration>
   <packageSources>
+    <add key="nuget.org" value="https://www.nuget.org/api/v2/" />
     <add key="Custom Packages for GHfVS" value="lib" />
   </packageSources>
+  <activePackageSource>
+    <add key="All" value="(Aggregate source)" />
+  </activePackageSource>
 </configuration>