Merge pull request #3969 from mloyd/mloyd-aws-cdk-ignore

Adding AWS-CDK ignore sample.

community/AWS/CDK.gitignore

@@ -0,0 +1,4 @@
+# CDK asset staging directory.
+# For more information about AWS-CDK, see  https://docs.aws.amazon.com/cdk/
+.cdk.staging/
+cdk.out/