Renamed the configuration keys
More configuration key renaming
Renamed comicUpdateInterva to lupdateInterval
MTConfigurationService test updates
Implemented basic validation for configuration options
Updated providers to include baseURL, earliestComicURL and latestComicURL properties
-[MTPersistenceService newComicForProvider:]
Stubbed MTNetworkingService and MTNetworkingServiceTests
Updated MTPersistenceServiceTests to use method swizzling instead of category overrides.
Added some test cases to MTNetworkingService: fetch latest, earliest, and comic with a specific identifier