Create and populate /docs folder for repo-default files

[joewxboy]

Project-wide issue & PR templates, CONTRIBUTOR/SECURITY/SUPPORT (community health) files, and possibly workflows/GHA can all have default versions created in this .github repository. It will also allow individual repositories to override the default if they wish by creating their own. This should make discoverability and maintainence much easier going forward.

Therefore, let's:

• Create a /docs folder
• copy/move the issue, PR, and _config.yml files from open-horizon.github.io repo to this one
• Create a CONTRIBUTORS.md file with "active" and "emeritus" sections with the below format

| Name | GitHub | email
|------|--------|------|----------------------
| Joe Pearson | joewxboy | joe.pearson@us.ibm.com

[Sukriti-sood]

@joewxboy This is very nice feature

[johnwalicki]

I don't understand how this Issue will work. Will ask @joewxboy to explain.

[joewxboy]

@johnwalicki a new(ish) technique is now available to us that solves three separate problems:

1. How do we create links in the right-hand column that give support resources to issue developers?
   The answer is Community Health Files stored in ".github" repo in "/docs" folder. Support is stored in well-known filename SUPPORT.md and GitHub will magically import and display in right-hand column on certain pages.
2. How do we create default or standard issue and PR templates for all repos in a github project, and also allow each repo to override as needed?
   The answer is to move the templates and related files to the ".github" repo, same folders.
3. Where do we create project-wide files like CONTRIBUTORS.md that apply to all repos?
   We are allowed to place in ".github" root folder or "/docs" folder. Putting it in /docs reduces the clutter, but hides the files somewhat. We can compensate by providing hyperlinks in the root folder README.md