Merge pull request #404 from mkuron/travis

Automated builds using Travis-CI

.travis.yml

@@ -0,0 +1,15 @@
+sudo: required
+
+services:
+  - docker
+
+script:
+- echo 'Europe/Berlin' | MAILCOW_HOSTNAME=build.mailcow ./generate_config.sh
+- docker-compose pull --ignore-pull-failures --parallel
+- docker-compose build
+- docker login --username=$DOCKER_HUB_USERNAME --password=$DOCKER_HUB_PASSWORD
+- docker-compose push
+
+branches:
+  only:
+  - master