Set up a Git repository for the product devfile registry

[johnmcollier]

Parent story: #320

We need to set up a Git repository to host the product devfile registry, for stacks that do not belong in the public community devfile registry at https://github.com/devfile/registry

• Create a git repository in the OpenShift org on Github for the devfile registry
  • Repository name will be redhat-developer/devfile-registry
• Set up the repository based on the devfile registry structure and add the JBoss EAP devfile stack to it
  • There should also be a dockerfile and build scripts under .ci/ for AppSRE's pipelines to build the registry
• Set up issue tracking for the new repository