Fixes issue #642.
- Re-implemented the fix for issue #642
- Looking much better, but still seeing some weirdness in iOS 5.x (the Index View doesn't show up and Shelf View shows up with incorrect orientation)
- Seems to work in iOS 6.0 without any issues
Merge pull request #670 from waywalker/landscape-only-issue-not-rotated-at-opening

Fixes issue #642.
Refactored methods to retrieve prices
Disabled alerts on App Store connection failure

Alerts won't pop up anymore when retrieving prices while there's no connection to the App Store.
Alerts will pop up as usual when the price retrieval is initiated by a user interaction.
Fixed Value Conversion Issue warning
Merge branch 'master' into paid-subscriptions

Conflicts:
	BakerShelf/PurchasesManager.h
	BakerShelf/ShelfViewController.m