XE-494: Convert XE documents to XWiki Syntax 2.0
XE-494: Convert XE documents to XWiki Syntax 2.0

* Fix warning/info macros which were inline instead of standalone. There's a pb with inline for these macros in the CSS used (they're taking too uch vertical space).

Merged from 2.0 branch

git-svn-id: cf27bad30c6b7316185bdac65b014e8c16cd40b6@23658 f329d543-caf0-0310-9063-dda96c69346f

xwiki/xwiki-enterprise,xwiki/xwiki-enterprise