Merge branch 'only_master_latest' into 'master'

Avoid any push to become the production image

See merge request !7

.gitlab-ci.yml

@@ -7,5 +7,18 @@ build:
     - docker-image-build
   script: "echo Done" # unused but this line is required by GitLab CI
   variables:
-    TO: $CI_REGISTRY_IMAGE:latest
-    FROM: docker:$DOCKER_VERSION # override Dockerfile's FROM line to match host docker version
+    TO: $CI_REGISTRY_IMAGE:$CI_BUILD_REF_NAME # put name of branch in image
+    FROM: docker:$DOCKER_VERSION # override Dockerfile's FROM line to match host docker version
\ No newline at end of file
+  except:
+    - master
+
+build_latest:
+  stage: build
+  tags:
+    - docker-image-build
+  script: "echo Done" # unused but this line is required by GitLab CI
+  variables:
+    TO: $CI_REGISTRY_IMAGE:latest # latest is the image used in production
+    FROM: docker:$DOCKER_VERSION # override Dockerfile's FROM line to match host docker version
+  only:
+    - master