Major refactoring

I have made a major refactoring.

• Now code is PEP-8 compliant.
• Fixed dozens of bugs.
• Improved some functions and general speed.
• Now minimum Python required version is 3.6.

Line chart improvement

0.6.0

Version 0.6.0

Error fixing

0.5.1

Update README.md

Improving some stuffs!

0.4.6

Update SOURCE

Color support added!

0.4.5

Added color test

Correction

0.4.4

Update setup.py

Correction

0.4.3

Update render.py

Correction

0.4.2

Version 0.4.2

A correction in check_data_type_integrity was doit.

Corrected an error.

Corrected an error in check_data_type_integrity.

Translation and optimization.

The code was translated to english.
The excesive use of try and except was removed.
The code was optimized and little glitchs were fixed.