Improve Continuous Intergration

Implement CI also for macOS. Test merge requests on our macOS 10.13 test system.
The pipline now consists of two steps with three different jobs. First the compliance
with the code formating rules is checked. If this step succeed the code is build and
tested on Linux and macOS. This step runs simultaneous on both platforms.

.gitlab-ci.yml

@@ -115,6 +115,39 @@ CbmRoot_Merge:
     - cat Dart.cfg
     - $PWD/Dart.sh MergeRequest Dart.cfg
 
+CbmRoot_Merge_macosx:
+  stage: build
+  tags:
+    - CbmRoot_macosx
+  only:
+    refs:
+      - merge_requests
+    variables:
+      - $CI_MERGE_REQUEST_PROJECT_PATH == "computing/cbmroot" && $CI_MERGE_REQUEST_TARGET_BRANCH_NAME == "master"
+  script:
+    - echo $CI_MERGE_REQUEST_SOURCE_PROJECT_PATH
+    - echo $CI_MERGE_REQUEST_PROJECT_PATH
+    - if [ "$CI_MERGE_REQUEST_PROJECT_PATH" != "computing/cbmroot" ]; then
+    -   echo "Should not come here"
+    -   exit 1
+    - fi
+    - echo $CI_MERGE_REQUEST_TARGET_BRANCH_NAME
+    - echo $CI_MERGE_REQUEST_ID
+    - echo $CI_MERGE_REQUEST_IID
+    - echo "export LINUX_FLAVOUR=macOS_10.13" >> Dart.cfg
+    - echo "export FAIRSOFT_VERSION=jun19p1" >> Dart.cfg
+    - echo "export FAIRROOT_VERSION=v18.2.0" >> Dart.cfg
+    - echo "export SIMPATH=/opt/fairsoft/\${FAIRSOFT_VERSION}" >> Dart.cfg
+    - echo "export FAIRROOTPATH=/opt/fairroot/\${FAIRROOT_VERSION}_fairsoft-\${FAIRSOFT_VERSION}" >> Dart.cfg
+    - echo "export BUILDDIR=$PWD/build" >> Dart.cfg
+    - echo "export SOURCEDIR=$PWD" >> Dart.cfg
+    - echo "export NCPU=4" >> Dart.cfg
+    - echo "export PATH=\$SIMPATH/bin:$PATH" >> Dart.cfg
+    - ls
+    - pwd
+    - cat Dart.cfg
+    - $PWD/Dart.sh MergeRequest Dart.cfg
+
 pages:
   stage: documentation
   image: alpine