Add gitlab CI automatic build

.gitlab-ci.yml

+image: ubuntu:18.04
+
+cache:
+  paths:
+    - technical-testing
+
+stages:
+  - build
+
+build:app:
+  stage: build
+  script:
+    - bash ci/00-install/01_install_dependencies.sh   # install system dependencies
+    - bash ci/01-build/01_build_documents.sh          # build documents
+  artifacts:
+    name: "technical-testing"
+    expire_in: 6 months
+    paths:
+      - technical-testing

build.sh

-#!/usr/bin/env bash
-
-#sudo apt-get install pandoc
-cat ./??_*.md > build/TECHNICAL_TESTING.md
-pandoc --from=markdown --to=odt --output=build/TECHNICAL_TESTING.odt build/TECHNICAL_TESTING.md
-pandoc --from=markdown --to=latex --output=build/TECHNICAL_TESTING.pdf build/TECHNICAL_TESTING.md

ci/00-install/01_install_dependencies.sh

+#!/bin/bash
+
+# We need to install dependencies only for Docker
+[[ ! -e /.dockerenv ]] && exit 0
+
+# Display debug in console
+if [ -n "${DEBUG}" ]; then
+    set -xe
+fi
+
+DEBIAN_FRONTEND=noninteractive
+TZ=Europe/Paris
+ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
+
+# Install missing dependencies
+apt-get update -yqq
+apt-get install -yqq pandoc texlive-latex-recommended texlive-latex-extra

ci/01-build/01_build_documents.sh

+#!/bin/bash
+
+# will run only in a docker env
+[[ ! -e /.dockerenv ]] && exit 0
+
+# Display debug in console
+if [ -n "${DEBUG}" ]; then
+    set -xe
+fi
+
+BUILD_FOLDER="technical-testing"
+mkdir -p "${BUILD_FOLDER}"
+
+# Concat all markdown documents
+cat ./??_*.md > ${BUILD_FOLDER}/TECHNICAL_TESTING.md
+
+# Build formatted documents
+pandoc --from=markdown --to=odt     --output=${BUILD_FOLDER}/TECHNICAL_TESTING.odt ${BUILD_FOLDER}/TECHNICAL_TESTING.md
+pandoc --from=markdown --to=latex   --output=${BUILD_FOLDER}/TECHNICAL_TESTING.pdf ${BUILD_FOLDER}/TECHNICAL_TESTING.md