The Lazy Data Source seems to all work now, but tests are still incomplete.  Many bugs in it were fixed by these changes:

• Explained in comments how -[ContentOutlineView outlineView:toolTipForCell:rect:tableColumn:item:mouseLocation:] overrides -[BkmxDocViewController
 tableView:toolTipForCell:rect:tableColumn:row:mouseLocation:]

• The noteChangedChildrenForStark: kludgey chain of drill-down methods has now been replaced by SSYManagedTreeChildrenChangedNotification.

• Added declaration of -[NSOutlineView itemAtRow:] to BkmxOutlineView.h to fix nonsense incorrect Xcode warnings that NSOutlineView does not implement this.

• More rework to the -checkAllProxies: mechanisms.

• Reworked how proxies are created.

• No longer leaks m_proxies and m_rootProxies

• Added kludge so that ContentOutlineView scrolls to the top now (-1 row - 1 point) in NSTableView (Scrolling)

• Reworked ContentProxy to handle dirty values in general instead of just dirty children, and replaced method -ensureChildren method -ensureDeeplyAndRegardlessly:

• Combined -setIndex: and -setParent: custom setters from Stark class into SSYManagedTreeObject.  Previously, the latter did not work because it was overridden by the former!

• Officially removed 0[Stark stealthilySetIndex:], which has not been used in recent commits.