Refactor GUI presentation

[rocher]

Introduction

Current GUI presentation of Project Euler Problems is a PoC. It has no complete information and element distribution on the screen must be improved.

DoD — First version of Project Euler GUI with complete information of the Problem and the solution, with a pleasant look and feel.

Tasks

• Add answer visualization as text
• Add legends for graphical elements
• Add more problem information: URL, difficulty ..
• Check font sizes on axes and GUI in general
• Fix labels on axes: display exponential notation for big numbers