Pull request to master

This method could use some improvements. Name is not consistent with what it does. It stores the new high score and also displays the label. Maybe it's better to separate these two tasks altogether. Give the responsibility of displaying to the label view instead.

```
- (void)endGame
{
...
BOOL isNewHighScoreAchieved = _scoreCurrent > _highScore;
[self shouldStoreNewHighScore:isNewHighScoreAchieved]; // responsible for storing the new high score
[self.labelView showGameOverWithScore:_scoreCurrent asNewHighScore:isNewHighScoreAchieved];
...
}
```