Pylint

[pmetras]

Linted the scanner code with Pylint and corrected most obvious errors and warning.

As I started using VS Code, I wanted to test the pylint option that starts pylint when a file is saved. It output many "problems" in the code and I decided to clean the simplest ones. I thought it would be simple but I had sometimes to change large pieces of code and was not as simple as thought. In the end, that's quite a large pull request...

Here is the summary of the changes:

• Unused variable or function parameters
• System imports before project imports
• No from module import *.
• Method should be a function
• Access to protected members
• Unecessary semicolon
• Space after comma
• No exception specified
• Boolean optimisation
• Too many public methods
• Dead code elimination
• Refactoring of code
• Creation of class Metadata to manage metadata functions.
• Started adding docstrings to have them displayed in the editor.

Now remain big pieces of code, particularly large methods that must be broken in smaller ones. Also I want to hide protected methods. When I have time, I'll try adding docstring to modules and functions.

[paolobenve]

good work!!! the code I wrote myself was quite approximative...

[paolobenve]

merged to master too, let's keep making all this stuff better in master