Add missing repo for elasticsearch-curator

Change-Id: I3934b608a73e882669835f1af8d4cfae1da5f964
diff --git a/linux/system/repo/elasticsearch.yml b/linux/system/repo/elasticsearch.yml
index 60f6fd0..2030114 100644
--- a/linux/system/repo/elasticsearch.yml
+++ b/linux/system/repo/elasticsearch.yml
@@ -5,4 +5,8 @@
         elasticsearch:
           source: "deb http://packages.elastic.co/elasticsearch/2.x/debian stable main"
           architectures: amd64
-          key_url: "https://packages.elastic.co/GPG-KEY-elasticsearch"
\ No newline at end of file
+          key_url: "https://packages.elastic.co/GPG-KEY-elasticsearch"
+        elasticsearch_curator:
+          source: "deb http://packages.elastic.co/curator/4/debian stable main"
+          architectures: amd64
+          key_url: "https://packages.elastic.co/GPG-KEY-elasticsearch"