ci(travis): use Build Stages

.travis.yml

@@ -1,13 +1,11 @@
 language: node_js
+
 services:
   - docker
-notifications:
-  email: false
+
 node_js:
   - 9
   - 8
-os:
-  - linux
 
 # Trigger a push build on caribou and greenkeeper branches + PRs build on every branches
 # Avoid double build on PRs (See https://github.com/travis-ci/travis-ci/issues/1147)
@@ -25,5 +23,10 @@ script:
 
 after_success:
   - npm run codecov
-  - npm install -g travis-deploy-once@4
-  - travis-deploy-once "npm run semantic-release"
+
+jobs:
+  include:
+    - stage: release
+      node_js: lts/*
+      script:
+        - npm run semantic-release