Add stages to GitLab CI

.gitlab-ci.yml

@@ -1,9 +1,21 @@
 image: python:3.5
 
-all_tests:
+stages:
+    - build
+    - lint
+    - test
+
+build:
+    stage: build
     script:
         - sh ./scripts/autoinstall.sh
+
+lint:
+    stage: lint
+    script:
+        - pep8 --count && eslint .
+
+test:
+    stage: test
+    script:
         - docker-compose run web python manage.py test
-    after_script:
-        - docker-compose exec -T web find . -type f -name '*.pyc' -delete
-    when: on_success