XWIKI-8541: Conflict on XWikiServerClassSheet in DW when installing XEM
XWIKI-8542: Conflict on XWikiServerClassTemplate in DW when installing XEM
XWIKI-8543: Conflict on XWikiServerClass in DW when installing XEM
XWIKI-8544: Conflict on XAppClasses.XWikiApplicationClass in DW when installing XEM
XWIKI-8545: Conflict on XAppTemplates.XWikiApplicationClassTemplate in DW when installing XEM
XWIKI-8546: Conflict on XAppSheets.XWikiApplicationClassSheet in DW when installing XEM