Possible regression from #fe260a8
Regression: -reloadData does not reload views any more even if the table is empty (see CPOutlineViewCibTest).
BUG: -removeTableColumn: error.
Conflicts:
AppKit/CPOutlineView.j
AppKit/CPTableHeaderView.j
AppKit/CPTableView.j
Fixed: An edited view no longer send its action (view-based) or commit its object value (cell-based) when unexposed.
Fixed: Cell based tables support for editing any control, not just textfield and buttons.