Add verbosity and classifier_by_lines

[nbeguier]

Features:

• Display probability of maliciousness with the function get_proba() in utility, used in classifier
• Add classifier_by_lines, which analyse a JS file line by line

[Aurore54F]

Hi, thank you very much for your improvements and comments! I did not have time to review them yet, but I'll keep you posted.

Cheers,
A.