chore(release): provide a way to create a local release with less grunt work (#429)

* docs(contributing): add information to update the changelog

* docs(changelog): add a first draft

it needs to contain the new PRs and only contains a not very nice version of the previous release to have an example

* chore(release): propose a way to locally generate a release

.versionrc.json

@@ -0,0 +1,3 @@
+{
+  "header": "### Actions Stale Changelog\n"
+}