Merge pull request #1125 from OctopusDeploy/v3feed

Use v3 Feedz NuGet api

Author: droyad

NuGet.Config

@@ -6,7 +6,7 @@
   <packageSources>
     <add key="NuGet.org v3" value="https://api.nuget.org/v3/index.json" />
     <add key="NuGet.org" value="https://www.nuget.org/api/v2/" />
-    <add key="feedz.io" value="https://f.feedz.io/octopus-deploy/dependencies/nuget" />
+    <add key="feedz.io" value="https://f.feedz.io/octopus-deploy/dependencies/nuget/index.json" />
     <add key="nuget.packages.octopushq.com" value="https://nuget.packages.octopushq.com/" />
   </packageSources>
 </configuration>