Arcade Mode UI Rework

We'll need to change the following about the page to be in line with the mock ups. This is all from page 28 of the rework document

• Keybindings to change between the different courses
• Scrolling box to display all the courses and their previews
• Best Times
• Keybind to pull up the leaderboard
• Higher Resolution Stage Previews
• Any Graphical Assets Required
• The ability to save and quit runs (disqualifies you from the leaderboards)
• The ability to restart a run from the main course screen