Refactor game retrieval functions

In order to fix the context bar, we'd need another game retrieval
function. This commit creates one game retrieval function with three
flag arguments, which covers all our needs elsewhere.

`nearest_game` is renamed `imminent_game` because that word better
explains that the function is getting games from the future.
Fix breakout bar.

The breakout bar now looks at the game in progress or most recent game.
If there are no games, we display an empty bar.
Fix decorators and validators in the 0 and multi-game cases.
Fix meal ticker.

The meal ticker also needed to only display results from this game.
Merge pull request #125 from jthemphill/new_fixes

Game-based fixes