Group projects

Yak shaving... I have a lot of projects and instead of going thru each one I "saved" time by creating this PR.

This change groups the projects on the edit page into sections for:
- Projects owned by the user
- Projects forked by the user
- Projects owned by an organization where the user is an admin
- Projects forked by an organization where the user is an admin

I didn't mess around w/ styling or behavior (e.g. collapsible sections), but they are grouped into HTML5 section elements so that wouldn't be hard to do.