tomcat generate ecs.yml (#1509)

* convert to ECS generated fields * update changelog, fix id in ecs.yml * update README.md

Author: leehinman

packages/tomcat/_dev/build/build.yml

@@ -0,0 +1,3 @@
+dependencies:
+ ecs:
+ reference: git@1.11

packages/tomcat/changelog.yml

@@ -1,4 +1,9 @@
 # newer versions go on top
+- version: "0.4.3"
+ changes:
+ - description: Convert to generated ECS fields
+ type: enhancement
+ link: https://github.com/elastic/integrations/pull/1509
 - version: '0.4.2'
  changes:
  - description: update to ECS 1.11.0