UPDATE MASTER SORT DOC

Create empty division node.

UPLOAD:
1. rs5.loc.gov/xmlcommon/eadwork/mfer_files/common/loc_divisions_ead_master_sort_01.xml
2. rs5.loc.gov/master/music/loc_divisions_authority_search/loc_divisions_ead_master_sort_01.xml
3. findingaids.loc.gov/eXist/db/search/xq/loc_divisions_ead_master_sort_01.xml
4. findingaids.loctest.gov/exist/db/search/xq/loc_divisions_ead_master_sort_01.xml