Adding .NET v4 to SDK definitions (#156)

Author: rlhagerm

aws_doc_sdk_examples_tools/config/sdks.yaml

@@ -230,6 +230,16 @@ Kotlin:
       api_ref:
         uid: "DotNetSDKV3"
         name: "&guide-net-api;"
+    4:
+      long: "&NETlong; (v4)"
+      short: "&NET; (v4)"
+      expanded:
+        long: "AWS SDK for .NET (v4)"
+        short: "SDK for .NET (v4)"
+      guide: "sdk-for-net/v4/developer-guide/welcome.html"
+      api_ref:
+        uid: "DotNetSDKV4"
+        name: "&guide-net-api;"
   guide: "&guide-net-dev;"
 PHP:
   property: php