Update "Clean and Prepare Data with Python" to fix deprecated content.

[ricardoprins]

There have been some changes to some of the packages used in the tutorial, and because of it, some of the material is either deprecated or will change very soon.

I am submitting a PR with the necessary changes - mainly changes to kwargs in specific methods, and removal of some graphics (seaborn's distplot was deprecated in 0.12, for instance; other positional arguments are no longer accepted as positional, having to be passed as kwargs)