Update CI to lint js too

.gitlab-ci.yml

 stages:
   - test
-  - syntaxe
+  - linting
   - doc
   - deploy
 
@@ -27,7 +27,7 @@ testing:
     - docker
 
 flake8:
-  stage: syntaxe
+  stage: linting
   image: python:3.6.5-jessie
   script:
     - pip install flake8
@@ -35,6 +35,14 @@ flake8:
   tags:
     - docker
 
+eslint:
+  stage: linting
+  image: pipelinecomponents/eslint:latest
+  script:
+    - cd frontend && npm run lint
+  tags:
+    - docker
+
 pages:
   stage: doc
   image: floawfloaw/plantuml
@@ -50,7 +58,7 @@ pages:
     paths:
       - public
     expire_in: 1 month
-  only: 
+  only:
     - master
   tags:
     - docker