Implemented rename, copy-paste and cut-paste for the thumbnails. Possible bug: although the .thumb directory is created using mkdir with 777 permissions, when elFinder tries to delete it, it throws an error stating that the folder is locked. Might be because I have the site data in /var/www which is owned by root.

git-svn-id: http://voronet.francu.com/repos/DEX@951 8d550267-2627-4c68-899f-85492a8dd5ca