Log Message:
waf: update to 2.0.6.

NEW IN WAF 2.0.6
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* Add Task.deep_inputs to enable further dependencies on input file tasks
* Set unit tests to depend on input file tasks instead of timestamps

NEW IN WAF 2.0.5
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* Force unit tests to depend on the executable creation time besides file contents
* Enhance the Eclipse project generator
* Update the cuda examples