Merge pull request #1883 from ubernostrum/document-deleted-manager

Fix namespace collision with deleted documents manager.
Fixing deleted_object*s*
Prevent last child spacing empty space side effect
Merge pull request #1885 from darkwing/deleted-objects

Fixing deleted_object*s*
Merge pull request #1886 from darkwing/main-center-clear

Prevent last child spacing empty space side effect
Use current kuma-lib to fix error.
Fix a typo in DeletedDocumentManager.