ReplayKit iOS 14.5 to 15.0 API Differences

RPError.h
Added RPRecordingErrorExportClipToURLInProgress
RPScreenRecorder.h
Added -[RPScreenRecorder startClipBufferingWithCompletionHandler:]
Added -[RPScreenRecorder stopClipBufferingWithCompletionHandler:]
Added -[RPScreenRecorder exportClipToURL:duration:completionHandler:]