expired view access is not cleared

[Evan Goldenberg]

When time limits are set for view access, the access is not cleared from the view once the access period is over. Access *does* appear to cease.

To reproduce:

- Create a view
- Set Public access for the view with an end time that is a few minutes away
- Wait for the access to expire
- External users can no longer access the view, but the owner's "My Views" page continues to list "public" for "who can see this view", and the expired access information is still present in the "Edit Access" page.

[Evan Goldenberg (naveg)]

A related issue is that the view access page allows you to specify access that has a stop date in the past.

[Evan Goldenberg (naveg)]

Fixed both of these on master.

Rather than setting up a cron job or doing extra database reads when a view is accessed, I decided to simply hide expired access on the view access page. When the view owner visits the page to change access, expired access will be deleted when the form is saved.