* WIP: Add TreeTableSource
* Improve expand/collapse
* Render branch/tree properly
* Simplify TreeTableSource to only allow one TreeView
* Add TestTreeTableSource_BasicExpanding test
* Add test combining checkbox and tree together
* Move tree example into main TableEditor scenario
(deleting TreeTableExample.cs)
* Mouse support for expanding/collapsing branches
* Make TreeTableSource work with CheckBoxTableSourceWrapperByObject<T>
* Add tests for mouse expand/collapse
* Improve quality of TableEditor scenario
* Fix mouse expanding not refreshing screen
* Fixed null reference when clicking in header lines
* Add null checks to scenario now it can show trees as well as data tables
* Switch to underscore prefix on private members
* Remove accidentally committed file
* Add setup/teardown to explicitly set driver checked/unchecked glyphs
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Co-authored-by: Tig <tig@users.noreply.github.com>
