Copy resume data in the event of operation failure
Copy resume data in the event of operation failure

The main purpose for this is so that the `resumeData` can be used when
initializing a new operation. In the event that the operation has
resumeData when initialized then instead of `re-downloading` it will
seamlessly continue the download.

SoneeJohn/SJURLSessionOperation,SoneeJohn/SJURLSessionOperation