More changes with unknown errors
Magical fix
MatchHistory CoredData Implementation

Added new NSURLSession addition that ensures synchronous data tasks.

DataManager now adds fetches and stores match history data.
HomeVC accordingly shows match history basic stats.

Note: layout of the core data entities are exactly the same.
Except for a summonerIndex attribute that points to where
the current summoner is in the participants array in match data.

Note: because for every match history of a summoner,
the corresponding match must also be fetched,
10 requests per 10 seconds Riot limitation blocks traffic.
For now, only 5 matches are pulled.
Added model classes and modified sign in behavior

NSManagedObject subclasses were added to the Model Classes folder.
signInWithSummoner: was modified to make its network request async.