update to centralized travis configuration

Author: jsvd

.travis.yml

@@ -1,16 +1,2 @@
----
-sudo: required
-language: minimal
-matrix:
- include:
- - env: ELASTIC_STACK_VERSION=5.x
- - env: ELASTIC_STACK_VERSION=6.x
- - env: ELASTIC_STACK_VERSION=7.x
- - env: ELASTIC_STACK_VERSION=7.x SNAPSHOT=true
- - env: ELASTIC_STACK_VERSION=8.x SNAPSHOT=true
- fast_finish: true
-#allow_failures:
-# - env: ELASTIC_STACK_VERSION=8.x SNAPSHOT=true
-# - env: ELASTIC_STACK_VERSION=7.x SNAPSHOT=true
-install: ci/unit/docker-setup.sh
-script: ci/unit/docker-run.sh
+import:
+- logstash-plugins/.ci:travis/travis.yml@1.x