Game persistence cache

@matthewhuff89 - Work on the GameEngine, cache set up for game persistence. Views aren't done yet, so displaying a live JSON representation of a game for now after joining a match.
OK, so here's why the Dalli.  But...WHY?  Was the app running slowly and you can prove it?  Or is this a "Caching is neat, let's try it?"  If the latter, I _would not do it_.  Pros don't do stuff because it's neat, they do what's neat because it's necessary.

Or, as :basketball: teaches:

The dunk exists for when your lane is clear and you need those two-points _for sure_.  It incidentally looks cool.  But you don't go for the dunk when Mutombo is guarding you.

![mutombo](https://cloud.githubusercontent.com/assets/50019/5569153/431c54a2-8f39-11e4-9415-c1a68ea41923.gif)