Calculate scores using Challenge.points + Show Cumulative Score

[scottBowles]

Instead of calculating a score of number correct, instead our score will be based on the points assigned to each Challenge.

We'll need to fix this on the scoreboard and on the review page.

Given this, we might also change the scoreboard to show cumulative points, whether on its own page, in a static part of that page, or otherwise. We could even have it show the cumulative points for each day, but that might start to get heavy. But also maybe not!

[scottBowles]

The first parts of this should be done now. Still need to display cumulative points somewhere. Tbh should be pretty easy, even with cumulative points for each day, since all the data is there. Just need to sum the points for the challenge set responses of the given player I think

[scottBowles]

Done