Charts

I've implemented a working Pie Chart on the weekly results page. It isn't the prettiest thing in the world yet, but it is functional. The tooltips aren't working but that appears to be a reported issue for pie charts on the angular-charts repository. 

Pie in the sky idea (get it?): Allow Dave to choose a team's real color using a color picker. Associate that color with the team. Then, for the pie chart each week, use the team's color as the color for that slice of the pie.