Create a getting started guide

[joshbressers]

We need a guide written that explains for new contributors how to get started. We should write such a guide with the assumption the people adding content are not overly familiar with GitHub, open source, or SBOM Everywhere

If we want to be inclusive we cannot be too descriptive.

[joshbressers]

An easy way to write this would be for someone to figure out how to stand up and modify the catalog and wiki projects