prepare for #4330


git-svn-id: https://forge.indepnet.net/svn/glpi/trunk@21584 35612d4c-9d10-0410-837c-bf9dd1be60d7
Add a new column in Document tab showing in ticket fixed #4330


git-svn-id: https://forge.indepnet.net/svn/glpi/trunk@21586 35612d4c-9d10-0410-837c-bf9dd1be60d7
Sort linked documents  fixed #1312


git-svn-id: https://forge.indepnet.net/svn/glpi/trunk@21588 35612d4c-9d10-0410-837c-bf9dd1be60d7