Passing tests

As reported in https://github.com/defunkt/zen/issues/5 tests were not passing. It seems that there was an extra spec file that was including a file that did not exist. Also, the tests were not properly defining WorkspaceView and they were looking for the `atom.workspaceView` to contain an element with the class `zen`. However, this package is actually adding the `zen` class to the `atom.workspaceView` itself.