Creating a clean graphics update

[mmcleod89]

• Added the sprites we have into each of the games
• Unified the buttons under a standard button prefab so that any changes made to the menu style update automatically
• Temporarily changed button colours for clarity against the background
• Added scrolling background and flickering flame behind the rocket for Star Collector
• Updated particle effect to use sprites
• Different cursors have been (temporarily) selected for eye, head rotation, and head position. Whatever icons we use should be consistent throughout all games.
• Some file reorganisation since we have an increasing number of prefabs.

Rocket Launch doesn't have a background yet, nor do we have any UI elements yet beyond the cursors.

[mmcleod89]

This one has no conflicts the base branch and so shouldn't be missing anything. The win screen buttons are still there and I haven't found any errors printed in the console while running the games but I'm still in the process of checking the build

[mmcleod89]

Build is working correctly as well! I think this is the best version to use for the demo

[K-Meech]

Thanks @mmcleod89 ! Can confirm that I can build the project now + don't see any errors 🎉 So I'll use this version for the demo