USe groupby instead of the seaborn estimator functionality (seaborn, exercise 5) #91

visualization_02_seaborn.ipynb; exercise 5

Use a bar plot to compare the victims for each day of the week with Seaborn directly (do not use the groupby).

Whereas we mostly use groupby pattern which is more general, the single exercise on estimator in seaborn makes it confusing. sticking to a single access pattern is more clear