Interface for creating and editing dashboards

[simonw]

This is currently only possible in the Django Admin. This will also implement edit permissions, taking over from #27.

Still todo:

• Form to save a dashboard as a saved dashboard
• If dashboard reloads with form errors, scroll down to the form
• "Edit dashboard" link that links to the Django admin
• Custom Django admin code to respect edit policies
• Saved dashboard pages should show their visibility and edit policies

[simonw]

I'm going to put this interface at at /dashboard/<slug>/edit/

Creating dashboards will start with a button on /dashboard/ - which will redirect the user to the new /dashboard/<slug>/edit/ page for further changes.

[simonw]

For the first non-alpha release I'm going to link to the Django admin interface for edit.

[simonw]

This means I need to write custom admin permission logic that takes the edit permissions and groups into account.

[simonw]

I'm going to allow super-users to reassign ownership of dashboards - but regular users will not be able to do that, even if they own the dashboard.

[simonw]

Spotted an edge-case: if a user isn't staff they will not be able to access the edit interface, no matter what the edit policy is.

[simonw]

That test failure turned out to be a Django version problem! Upgrading to the latest Django in my dev environment gave me the ability to replicate the bug.