add testcases for Simon's actions at the start of a new round

the testcases are failing due to missing functions pickRandomColor() and nextRound()
add missing functions pickRandomColor() & nextRound()

the testcases are now failing like expected
work in progress: implement Simon's actions at the start of a new round

TODO:
- replacing pickRandomColor by a spy didn't work, and attempting to replace the prototype early on didn't work either...
- also some inconsistencies with function() and function () to address in previous commits