Create a dedicated section in the docs describing the spec development process

[khughitt]

As we are going through the process of updating the specs and hammering out the _process _ for how that is done, it seems like it would be a good time to update the docs to include a section describing this.

Some things that could be good to include:

• spec revision process / rules (including @peterdesmet 's suggestions here)
• governance model / role of working group
• schedule / indication of frequency of expected changes
• how one should reach out to get involved / become a part of the working group
• pointer to any current/ongoing efforts, and/or milestones planned for the future

[peterdesmet]

I think we need this rather soon. 👍

[roll]

@sapetti9 has already started it here - https://datapackage.pages.dev/standard/governance/ :+1: