Interface for adding tests to the suite(s)

[seancribbs]

The days of hand-editing db/seeds.rb and adding migrations for non-schema tasks should be over! We should be able to:

1. Add tests to suites in bulk
2. Modify existing test definitions (and swaths of them?) to add or remove tags.
3. Do bulk additions/modifications in simple, repeatable, deterministic, and obvious (from a UI perspective) ways.
4. Update Ember models automatically from response.