Overlay does not pre-load next game's info

[TristanDebrunner]

Describe the bug
The overlay code does not fetch the info about the upcoming game until after it has switched to the next game screen. While it is loading the data, it incorrectly shows the data from the previous game.

Expected behavior
It should preemptively fetch the data during the final scores period, so that it can be immediately displayed in the next game screen. If data has not yet been received, it should show placeholder data, not the data from the previous game.

[TristanDebrunner]

Fixed by #173