Minor change to allow using `this` for jasmine suite

Especially when writing coffeescript tests it is common to use `this` for variables in scope 

A very minor change to allow this style

```
describe "a feature", ->
    async.beforeEach -> 
        @mockFoo = jasmine.createSpy()
        @sut = blah(mockFoo)

    it "calls foo", -> (expect @mockFoo).toHaveBeenCalled()
```