Day04 - Updates post-testing

[matboivin]

Global notes:

• ex04 is simpler than ex03

ex00:

ex01:

ex02:

• 1. Is it necessary to handle errors?
• 2. Drop duplicated values and update the result in the example (0.02307969707897584) to 0.01935634328358209.
  See: Day04 - Pandas #5 (comment)

ex03:

ex04:

• 1. The examples are a bit misleading: sp.where(2162) is not in the dataset and sp.when('Atlanta') olympic games took place in 1996, neither in 1903 nor 2042.
  It should be mentioned not to trust the examples.
  See: Day04 - Pandas #5 (comment)

ex05:

• 1. If duplicated medals are not handled for the team games, this exercise is too similar to ex03.
• 2. The CSV data is not up-to-date.
• 3. Precise in the instructions if duplicated medals per team games should be handled and add an example from the dataset.
  If duplicated medals are dropped: France 2008: {'G': 25, 'S': 24, 'B': 28} -> {'G': 7, 'S': 16, 'B': 20}
  See: Day04 - Pandas #5 (comment)

ex06:

• 1. Add concrete examples:
  Maybe add some plots (mathplotlin.pyplot.hist()) screenshots for more clarity. All images must be put in an assets directory at the root of the day folder.
• 2. The word feature from ML and data science terminology can be a little bit confusing at the beginning.

ex07:

• 1. Add concrete examples:
  Maybe add some plots (mathplotlin.pyplot.hist()) screenshots for more clarity. All images must be put in an assets directory at the root of the day folder.

[maximechoulika]

Let's put on the side the last comment and merge this.