Improve test reliability

The fibonacci example test should now succeed reliably, and the dependency on ```turtle_tf_demo``` is no more.
```turtle_tf_demo``` crashed sometimes, causing the tf example test to fail. Since the test only checks a single tf's rotation quaternion, a static_transform_publisher can replace it.

I also added a launch file that could be used instead of the shell script.

This PR should fix #115 and #114