Merge branch '8-build-on-riseclipse-ci' into 'master'

Add .gitlab-ci.yml file

Closes #8

See merge request !4

.gitlab-ci.yml

+
+stages:
+  - build
+  - test
+  - deploy
+
+build:
+  stage: build
+  script:
+    - "pushd .."
+    - "if [ -d RiseClipseDeveloper ]; then cd RiseClipseDeveloper ; git pull ; else git clone https://gitlab.centralesupelec.fr/RiseClipseGroup/RiseClipseDeveloper.git ; fi"
+    - "popd"
+    - "mvn clean install"
+  tags:
+    - riseclipse
+