added initial release documentation

docs/release.md

@@ -0,0 +1,23 @@
+## update changelog, create signed tag and push to github
+
+```
+contrib/generate-changelog > CHANGELOG.tmp
+mv CHANGELOG.tmp CHANGELOG.md
+$EDITOR CHANGELOG.md # verify version is correct and tweak 
+VERSION=$(head -1 CHANGELOG.md | awk '{print $2}')
+git add CHANGELOG.md
+git commit -m "changelog: updated for $VERSION release"
+git tag -s -m "$VERSION release" $VERSION
+git push github
+git push github --tags
+```
+
+## build docker image, test and publish (to be done automatically via ci)
+
+```
+docker build -t tklx/mongodb:$VERSION -t tklx/mongodb:latest .
+IMAGE=tklx/mongodb:$VERSION bats --tap tests/basics.bats
+docker push tklx/mongodb:$VERSION
+docker push tklx/mongodb:latest
+```
+