Summary: Fixes T9762. Ref T10246. **Disabling Bindings**: Previously, there was no formal way to disable bindings. The internal callers sometimes check some informal property on the binding, but this is a common need and deserves first-class support in the UI. Allow bindings to be disabled. **Deleting Interfaces**: Previously, you could not delete interfaces. Now, you can delete unused interfaces. Also some minor cleanup and slightly less mysterious documentation. Test Plan: Disabled bindings and deleted interfaces. Reviewers: chad Reviewed By: chad Subscribers: yelirekim Maniphest Tasks: T9762, T10246 Differential Revision: https://secure.phabricator.com/D15345