Some initial changes for SummonerVC
Added new prof icons
SummonerVC now uses SummonerManager.

VC's data is no longer from DataManager,
but DataManagaer's methods have not yet been deleted.

Upon pushing a SummonerVC, the newly pushed VC immediately
calls its SummonerManager to refresh matches asynchronously.
Once the fetching is done, SummonerManager gives VC
the matches and VC updates header & reloads tableview.
NOTE: during this time an activity indicator should show.
Right now, the speed is too fast to notice, but under
slow internet connections, UI will respond, but will not
tell the user of what is happening.

TODO: Detect scroll of TableView to load more matches
once user hits bottom of the match history.
Small readability changes

Implemented class method in DataManager that takes care of
fetching summoners given a name, region, success&fail handler.
Makes code more readible in classes that actually make use of
the fetched summoners data.
(SignIn & SummonerVCs have been modified accordingly).

Fiddling with AppDelegate to see if app enters SummonerVC immediately
given an already registered user, but does not seem to do so.

TODO:
- SummonerManager does not seem to be saving summoners to core data
- Back button does not show for any summoners searched
Merge branch 'dennis' into chris