improve inclusiveness by building a community of users

In order to improve engagement with the community we need clear guidance in the form of documents in the project root directories to help users to be able to contribute. In particular the narayana repo is missing the following information:

• the CONTRIBUTING.md file does not say how to find issues to work on, we should use a label for this in our issue tracker (“good first issue” is the recommendation)
• CODE_OF_CONDUCT.md
• SECURITY.md
• CODEOWNERS link (we should use the component lead field in the project issue tracker for this

The relevant repositories are:

https://github.com/jbosstm/narayana

https://github.com/jbosstm/quickstart

https://github.com/jbosstm/performance

https://github.com/jbosstm/jboss-transaction-spi

https://github.com/jbosstm/documentation