Merge branch 'dev-dockerhub' into 'master'

Dev dockerhub

See merge request m.boileau/tp-gitlab-ci!1

.gitlab-ci.yml

 stages:
   - build
   - test
+  - release
+
+variables:
+  CONTAINER_TEST_IMAGE: boileaum/rosen:$CI_COMMIT_REF_NAME
+  CONTAINER_RELEASE_IMAGE: boileaum/rosen:latest
+
+before_script:
+  - echo $DOCKERHUB_PASSWD | docker login -u boileaum --password-stdin
 
 b:docker:
   stage: build
   tags:
     - shell, docker
   script:
-    - docker build --pull -t boileaum/rosen:latest -f ./docker/Dockerfile-rosen .
+    - docker build --pull -t $CONTAINER_TEST_IMAGE -f ./docker/Dockerfile-rosen .
+    - docker push $CONTAINER_TEST_IMAGE
 
 t:docker:
   stage: test
   tags:
     - shell, docker
   script:
-    - docker build --pull -t boileaum/rosen:latest -f ./docker/Dockerfile-rosen .
-    - docker run boileaum/rosen /bin/bash -c 'pytest -v'
+    - docker pull $CONTAINER_TEST_IMAGE
+    - docker run $CONTAINER_TEST_IMAGE /bin/bash -c 'pytest -v'
+
+r:docker:
+  stage: release
+  tags:
+    - shell, docker
+  script:
+    - docker pull $CONTAINER_TEST_IMAGE
+    - docker tag $CONTAINER_TEST_IMAGE $CONTAINER_RELEASE_IMAGE
+    - docker push $CONTAINER_RELEASE_IMAGE
+  only:
+    - master