New set of functions for CI

gitlab/after_build.sh

gitlab/after_deploy.sh

gitlab/after_docs.sh

gitlab/after_test.sh

gitlab/after_wheels.sh

gitlab/before_build.sh

gitlab/before_deploy.sh

gitlab/before_docs.sh

gitlab/before_test.sh

gitlab/before_wheels.sh

gitlab/build.sh

gitlab/deploy.sh

gitlab/docs.sh

gitlab/functions.sh

gitlab/install.sh

gitlab/test.sh

gitlab/wheels.sh

templates/ci-for-cxx-extensions.yml

templates/ci-for-python-only.yml