Update Supporting Docs

- Update README.md
- Added issue and PR Templates
- Added CONTRIBUTING.md, SECURITY.md, CODE_OF_CONDUCT.md, SUPPORT.md

These changes are made based on the upstream approved documentation https://github.com/jenkinsci/.github with a few additions.

.github/pull_request_template.md

@@ -0,0 +1,34 @@
+<!-- 🎉🎉🎉 Thank you for the PR!!! 🎉🎉🎉 -->
+
+# Changes
+
+<!-- Describe your changes here- ideally you can get that description straight from
+your descriptive commit message(s)! -->
+
+# Submitter Checklist
+
+These are the criteria that every PR should meet, please check them off as you
+review them:
+
+- [ ] Includes tests (if functionality changed/added)
+- [ ] Includes docs (if user facing)
+- [ ] Commit messages follow [commit message best practices](https://github.com/jenkinsci/kubernetes-operator/blob/master/CONTRIBUTING.md#commit-messages)
+
+_See [the contribution guide](https://github.com/jenkinsci/kubernetes-operator/blob/master/CONTRIBUTING.md) for more details._
+
+
+## Reviewer Notes
+
+If API changes are included, additive changes must be approved by at least two [OWNERS](https://github.com/jenkinsci/kubernetes-operator/blob/master/OWNERS) and backwards incompatible changes must be approved by [more than 50% of the OWNERS](https://github.com/jenkinsci/kubernetes-operator/blob/master/OWNERS).
+
+# Release Notes
+
+```
+Describe any user facing changes here, or delete this block.
+
+Examples of user facing changes:
+- API changes
+- Bug fixes
+- Any changes in behavior
+
+```