Adding step for implementing RFCs

Created by: christinaforney

Adding this to start the conversation about putting RFCs into action. Something that has been brought up by the team (one example) is that once an RFC is being worked on, there is no place to track what parts of that RFC have been implemented, are in progress, or that we might want to prioritize at a later time.

As a PM it is also hard for me to keep track of all the moving pieces that have been implemented and not. This creates a space to link together all the work that is done for an RFC where the work is being done (and not in a google doc).

Only RFCs that are going to be worked on, or are starting to be worked on should have tracking issues created to avoid a proliferation of GitHub issues that are not currently prioritized in the project roadmap.