v1.2

Refactored code for MVVM design pattern.
Added styles and graphic effects to GUI.
Added multiprocessing for efficient json data parsing.

First app version after code refactoring

Finish code refactoring

Used some predefined modules to:

• enhance GUI list of object performance - the deletion of objects is easier
• decouple code for GUI building from code for logic implementation
• ensure event-driven automatic synchronization of values between backend
  variables and frontent GUI PyQt5 object
• make all the code cleaner and easier to maitenance.