Fixed: In CPTrace, fixed error when an argument was not a cappuccino object.

Arguments such as CGPoint, CGRect and functions are now correctly
printed to the console.
New: -enumerateAvailableViewsUsingBlock: and private -_enumerateViewsInRows:columns:usingBlock: and -_enumerateViewsInRows:tableColumns:usingBlock: methods.
New: preparedViewAtColumn:row:

These methods allow to enumerate visible data views or data views in specified columns and rows.
-enumerateAvailableViewsUsingBlock: is the counterpart of cocoa's -enumerateAvailableRowViewsUsingBlock: except that it enumerates data views instead of CPTableRowView and the block has an additional column parameter.

This commit reverses the way views are stored and accessed in the table view: rows>columns instead of columns>rows.
Applied the second method where it is relevant, making the code more compact and readable.
Fixed: -reloadDataForRowsIndexes:columnIndexes: behavior.
Fixed: Column dragging performance, content binding performance.

After this commit, -reloadDataForRowsIndexes:columnIndexes: reloads the data and the data only.
The -reloadData method no longer tries to reuse the views, instead it just reloads the data for visible views.
To flush and reload the views cache for visible rows, use _reloadDataViews.
To internaly layout the views geometry, use _layouViewsForRowIndexes:columnIndexes:

In CPTableView dragging column code, relayout the views whose frame changed instead of reloading everything.
Fixed: After drag, views were cached.

This commit reverts #1478. It appears it is a bad idea to enqueue
visible views. The views generally stay in the cache forever and they
are repeatedly asked to be removed from the table at each load, causing
a performance penalty.
Fixed: editingColumn and editingRow return the correct index in view based tables
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.
Fixed: noteHeightOfRowsWithIndexesChanged: was not showing immediatly row height changes.

Todo: instead of reloading everything we should be able to just
relayout frames for visible views and then tile.
Fixed: selectColumnIndexes:byExtendingSelection: returns early when there is no change in columns selection

Before this change, rows could be unselected even if the columns
selection did not change.
Fixed: -moveColumn:to: now preserve selected columns
Fixed: Starting a column drag is now faster.
Fixed: When dragging a selected column, selection is now drawn on the dragging view and the cursor is the closed hand.
Fixed: When dragging a table column, underlying columns were sliding according to the tracking location instead of the column lateral edges.
Fixed: In CPTableView, the drop indicator for rows could appear when dragging a column.

This commit creates directly the dragging column instead of relying on
built-in drag&drop. Also fixes a bug where the drop indicator would appear when
dragging a column if some rows were previously drag&dropped.
Fixed CPOutlineView -reloadData and _layoutViewsForRowIndexes:columnIndexes: subclassing.
Fixed CPOutlineView subclassing when settting CPThemeStateSelectedDataView
Fixed CPOutlineView dragging column subclassing