Add lib and integration to spec dir

Some iOS rspec tests launch the simulators.  These examples are disruptive because the simulator steals keyboard focus.  Other iOS tests, like those that target physical devices, take a long time to run.

* If a test is short-running, put it in spec/lib.
* If a test is long-running (more than ~5 seconds), put it in spec/integration.
* If a test steals application focus, put it in spec/integration.

### Guard

```
$ be guard
```

Guard will watch for changes in the lib/calabash and spec/lib directories.  When a change occurs, it will run the rspec tests.  You can get immediate feedback via growl notifications.