feat(gitlab-ci): automatic release creation with semantic-release

Create new release when merge requests are merged into the $STABLE_BRANCH branch.

• templates/Release/Semantic-release.yaml: run semantic-release with the latest EOLE container for $STABLE_BRANCH branch if one of its configuration is present.

• .gitlab-ci.yml: execute a new stage release for semantic-release.

• release.config.js: create docs/CHANGELOG.md and publish new releases on Gitlab. Mangle commits to have links for users, issues and commits id.

• release-rules.js: create semantic version update rules based on docs/CONTRIBUTING.md.