GitHub Issues Workflow for Chef

This RFC codifies the workflow of Chef maintainers while maintaining issues and contributions for Chef.

Special thanks to @btm / @lamont-granquist / @danielsdeleo / @mcquin / @adamedx / @jdmundrawala  who has helped put the first version come together.
This is also very wordy. Could we just say:

> It is the responsibility of the **Chef maintainers** to identify the subcomponent category for each contribution or bug report. Some subcomponents may have different workflows that those outlined in this document.