[katas] update notes
[katas] update notes

raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning,raventid/coursera_learning