Update beats framework to 265ab8b

NOTICE.txt

@@ -245,13 +245,37 @@ SOFTWARE.
 --------------------------------------------------------------------
 Dependency: github.com/elastic/beats
 Version: master
-Revision: 7c338ce879cf27958c926d70b89ec9385a09e288
+Revision: 265ab8b22e9e0b7734f9f297e4fbe3bcf6dd7015
 License type (autodetected): Apache-2.0
 ./vendor/github.com/elastic/beats/LICENSE.txt:
 --------------------------------------------------------------------
 Apache License 2.0
 
 
+--------------------------------------------------------------------
+Dependency: github.com/elastic/ecs
+Revision: 337ddd4674d6a28da97e6d19010c04c43db09e58
+License type (autodetected): Apache-2.0
+./vendor/github.com/elastic/ecs/LICENSE.txt:
+--------------------------------------------------------------------
+Apache License 2.0
+
+-------NOTICE.txt-----
+Elastic Common Schema
+Copyright 2018 Elasticsearch B.V.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
 --------------------------------------------------------------------
 Dependency: github.com/elastic/go-lumber
 Revision: 616041e345fc33c97bc0eb0fa6b388aa07bca3e1

_beats/libbeat/_meta/fields.common.yml

@@ -4,6 +4,10 @@
   description: >
     Contains common beat fields available in all event types.
   fields:
+    - name: agent.hostname
+      type: keyword
+      description: Hostname of the agent.
+
     - name: beat.timezone
       type: alias
       path: event.timezone