Update/replace checkpoint system

[bzier]

Deficiency:

The recently introduced checkpoint system (#22) utilizes the mini-map to detect character progress. This is imprecise and challenging due to the variations in the maps for each course (overlap, crisscrossing paths, off-course driving / shortcuts, etc).

But wait...

There is an alternative HUD view in Mario Kart which presents character progress by drawing a line around the edge of the screen. This line is drawn in one of three colors that designates the current lap (see notes below).

So...

Rather than sampling the mini-map and needing to maintain checkpoint locations for each course independently, this mode can be used to provide a consistent representation of progress on all courses (including the 'unknown progress' on Yoshi Valley). Additionally, it consistently and accurately reflects progress even as the character drives off-course and/or takes shortcuts, and it un-draws the colored lines when the character drives backwards. These advantages make it a significant enhancement over the current system.

Notes:

• C-Right (right thumbstick right on Xbox Controller) to cycle HUD views
• Coordinates:
  • Upper left - (64, 36)
  • Lower right - (585, 445)
• Laps:
  • 1 - Blue (0, 0, 255)
  • 2 - Yellow (255, 255, 0)
  • 3 - Red (255, 0, 0)

[bzier]

The committed implementation is mostly complete, however there are still some changes necessary.

Still left TODO:

• Post-race menu retry will result in racing against the best prior race's ghost, which messes up the progress detection (both the current character and the ghost draws their progress on the HUD)
  • Doing a driver/course change wipes the ghost
• Implement some sort of backward/reverse detection & punishment
• Update end episode detection since now we can detect immediately (partially done)