Update CastVideos-iOS sample to 2.4.0 SDK

- Remove GCKDeviceFilter
- Add some extra GCKDeviceManagerDelegate methods
- Take advantage of additional status property in device list
- Removed unused settings icon
- Fixed issue with thumbnail on local player not loading
- Updated to use deviceManager:didSuspendConnectionWithReason for network status

Change-Id: I126ef3bb19120efcfa53eb8d01974a2e8983ee6e