fibonacci.example.js: add timeout to give rosbridge time to subscribe the feedback topic
replace unreliable turtle_tf_demo with a static_transform_publisher

The tests only check a single tf anyway, and the static publisher is more reliable
add launch file for example setup

This provides a cleaner way to start (and kill) all the nodes required for the tests
Merge pull request #119 from T045T/improve_tests

Improve test reliability