Benjamin-Dobell/Heimdall — pull request #240 by iamtag (2014-11-04 03:35:56+00:00)
Title: Auto detect kEmptyTransferBefore and After

use below method to detect this differents,
call kEmptyTransferBeforeAndAfter in SEND_TOTAL_BYTES of flow,
if fail at after, it is only support kEmptyTransferBefore;
else it is only support kEmptyTransferAfter.