start of RecentlyPlayed

Loads in the json file, and returns game objects
include RecentlyPlayed
Merge branch 'master' into recently-played
add a unique() method to Array
add serialization to Game
include extensions
retain games array and just load it in load()
don't do anything if we don't have the data file
write the file
add a game

This adds the game to the top of the stack, makes sure the list is
unique, trims it to only 6 entries, and saves it.
add a game to the recently played list
Merge pull request #5 from maddox/recently-played

Recently Played