[DS-1686] Support new version of Biblio-Transformation-Engine for the batch import

The new version v0.9 of BTE is out (https://github.com/EKT/Biblio-Transformation-Engine). 

The current batch import (from BTE) code (+ the XML Spring configuration) needs to be updated to support this new version. 

DSpace documentation on batch import (from BTE) will also need an update.