Properly Comment the Code

[VincenzoFerme]

Comment all the choices in the code for which a comment might help to understand the why. Although it is tricky to decide what comment and what not to comment, a suggestion can be to comment all the code that after a couple of day you wrote need more than 5 seconds to grasp what the code is doing. For sure algorithms must be commented and documented in the most important steps.

See also #13