Add ability to delete projects

[nmashton]

Once a project is created, as far as I can tell, there's no way to delete it. That is definitely a bummer.

Proposal for fixing

• [x] Ability to put project into deleted state (logic layer + API)
• [x] Do not display such projects on user view or dashboard
  • Maybe for dashboard we still display but greyed out
• [x] Update dashboard with relevant UI to do deletion

Extras

• [ ] Trash page where you view your deleted DataViews
• [ ] Change name of project (so that new projects can be created with this name ...)
  • Propose we add "deleted-{random-string}" to name of project
  • Not completely trivial in that we also have to move on disk (name is unique id essentially)
• [ ] Undelete support
• [ ] Purge support - Ability to purge project (completely delete)

Estimated time: 4-6h

[rufuspollock]

why?

[nmashton]

See the other issue I just raised: while trying to make a screencast about TimeMapper, over the course of multiple takes, I ended up repeatedly creating projects with the same dataset. Each time I did this, I had to invent a new slug, and they soon got quite contrived. Also, the pileup of similarly-named projects on my user page became conspicuous as I kept filming.

[rufuspollock]

This is in progress and will be deployed soon we hope.

[rufuspollock]

This is the most requested issue by a way via email and twitter.

[rufuspollock]

NOTE: Have not done any of the extra stuff!