`test_clockgen.py` is missing `phase_delay` argument

[ksjh]

Hi, thank you for your work. It works great, but new users might be confused at first, since test_clockgen.py does not work without an argument for phase_delay in setupMultisynth(). I could generate a pull request, but I am not sure if you prefer a fix for the example code or a default value for the parameter phase_delay in the library.

I would also suggest to calculate all the printed texts in the example file using variables. I noticed that test_clockgen.py prints Set Output #2 to 1.0e+06 Hz, when, in fact, the output is 2.0 MHz.