Releasing the Jaeger Operator for Kubernetes

Make sure you are using an operator-sdk newer than 0.10.0
Make sure the versions.txt file is up to date
Make sure the new version is present at pkg/upgrade/versions.go
Prepare a changelog and get it merged. A list of commits since the last release (v1.15.1 in the following example) can be obtained via:
```
$ git log --format="format:* %s" v1.15.1...HEAD
```

Test!

export BUILD_IMAGE_TEST="${USER}/jaeger-operator:latest"
export BUILD_IMAGE="${BUILD_IMAGE_TEST}"
make all

Tag and push

git checkout master ## it's only possible to release from master for now!
git tag release/v1.16.0
git push git@github.com:jaegertracing/jaeger-operator.git release/v1.16.0

Apply generated OLM catalog files to operatorhub.io
- Clone the operatorhub repo
- Run make operatorhub
  - If you have hub installed and configured, it will open the necessary PRs for you automatically. Hint: dnf install hub works fine on Fedora.
  - If you don't have it, the branches will be pushed to origin and you should be able to open the PR from there