Enable explicit Tika content transform for OOXML files
Allow the Excel transformer (which does CSV as well as text/html) to handle .xlsx as well as .xls
Also update the .doc parser test to ensure that the older word 6 and word 95 files are correctly handled too
git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@20781 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
