Use jasmine.async lib to simplify async tests

Problem: Jasmine 2 changed the way async tests are written in favor of a `done` callback (as mocha does), deprecating the previous `runs/waitsFor` paradigm. Until all tests are migrated to this new paradigm, we can't use jasmine 2.

Solution: Use [derickbailey/jasmine.async](https://github.com/derickbailey/jasmine.async)'s AsyncSpec to get the `done` callback style while still running jasmine 1.x. When all specs are migrated this way, upgrading to jasmine 2 should be as simple as `s/async\.(it|beforeEach|afterEach)/\1/` (and then removing the unused AsyncSpec stuff).

Only one spec was migrated for now, but more will come! :)