Fixing End Game Messaging

#### What's this PR do?
The end-game messages that users get need to be evaluated on a per user basis. So different individuals could get different messages depending on how their game plays out.

#### Where should the reviewer start?
- Edits in competitive-stories.json are just so it matches up with the test story being setup in Mobile Commons.
- `addPathToStoryResults`: Evaluating for the end level group message requires it knowing all the opt-in paths users have been sent to. So this method lets us save opt-in paths to the story_results array. Previously, users would need to answer in response to a path in order for it to get add to the story_results.
- `checkResultType` parameter added to `getEndLevelMessage`: Came across a scenario where conditions would just be easier to set and be more robust if it could match against opt-in paths instead of user answers. This allows for that to be specified... though not using it yet until an actual game config comes around where we'll need to.
- The changes in `userAction` are mostly just to get `getEndGameMessage()` to be called for each user in the game instead of just the last user who responded.