Item12907: fix reparenting using drag&drop 

also:
- brought back normal web form in a slimmed down version
- collect all uncategorized topics in the TopCategory -> new OBJECTVERSION 0.83

Item12908: added a category-based virtual filesystem for WebDAVContrib/FilesysVirtualPlugin



git-svn-id: http://svn.foswiki.org/trunk@17680 0b4bb1d4-4e5a-0410-9cc4-b2b747904278