split out stages for travis

.travis.yml

@@ -1,9 +1,15 @@
 services:
   - docker
 
+jobs:
+  include:
+    - stage: "Build and Push"
+      name: "Build"
       script:
         - docker build -t boerderij/varken:$TRAVIS_BRANCH .
         - docker images
+    - name: "Push"
+      script:
         - echo "$DOCKER_PASSWORD" | docker login -u "$DOCKER_USERNAME" --password-stdin
         - docker push boerderij/varken:$TRAVIS_BRANCH