Adding game icon

[PBWiseman]

Describe your changes

Adding an icon for our game. This will be used for the .exe file and when in the taskbar

Issue number and link

194

Checklist before requesting a review

• [x] I have performed a self-review of my code
• [x] I have written any applicable tests
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] This complies with the product coding guidelines

[PBWiseman]

Added an icon to the game files and to the readme. Would love feedback on how people like it. The icon shows up both on the .exe and in the task bar when the game is open. You need to build it in a new folder so the cache doesn't use the old icon