Automate post release (#655)
Automate post release (#655)

* Add script to update changelog after release

* update_changelog_post_release script now adds the git diff at the end of the file

Also the script should be idempotent now.

* Fix wrong check for [Unreleased] header in scripts/update_pomxml_after_release.sh

* Added script to automatically bump the version in pom.xml

* Added a post-release make target to update changelog and pom.xml

* Do not fail in update_pomxml_after_release.sh if there is no java package

* Update documentation about post-release

* Apply review changes

* Move post-release logic to the java template

cucumber/gherkin-go,cucumber/gherkin-go,cucumber/gherkin-go