Draw UML class diagrams

[Derek-Frevel]

• Started a shared UML diagram using Figma
• Added QRScanner class
• Added ScoringSystem class

[Derek-Frevel]

• Added MainActivity, ListviewFragment, CustomList, <> CodeListListener classes
• Added a legend on the side of the UML to describe different class roles using colours
  • Model Class - Orange
  • Database Class - Light Purple
  • View Class - Light blue
  • Controller Class - Red
• Colour-coded most classes already in the diagram.

[Derek-Frevel]

• Added some empty classes to the diagram ready to be filled out
• Reserved some space on the diagram for player profile searching
• Reserved some space on the diagram for map browsing

[charvidhamija]

Added Database class