[NEW]New Wiki argument Variables, to help in scenarios of managing iso9001-powered documentation systems and such, where you need to expose some info like 'last version number', 'last author', and 'last modif' (for wiki pages and/or tracker items) to the wiki page with a special header to include this information. This way, wiki pages can be printed easily conforming the iso9001 document specifications, etc. Ref: http://dev.tiki.org/item5112

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@49602 b456876b-0849-0410-b77d-98878d47e9d5