Add cloud to S3/EC2 plugin docs

docs/plugins/discovery-ec2.asciidoc

@@ -3,6 +3,8 @@
 
 The EC2 discovery plugin uses the https://github.com/aws/aws-sdk-java[AWS API] for unicast discovery.
 
+*If you are looking for a hosted solution of Elasticsearch on AWS, please visit http://www.elastic.co/cloud.*
+
 [[discovery-ec2-install]]
 [float]
 ==== Installation

docs/plugins/repository-s3.asciidoc

@@ -4,6 +4,8 @@
 The S3 repository plugin adds support for using S3 as a repository for
 {ref}/modules-snapshots.html[Snapshot/Restore].
 
+*If you are looking for a hosted solution of Elasticsearch on AWS, please visit http://www.elastic.co/cloud.*
+
 [[repository-s3-install]]
 [float]
 ==== Installation