Revert Tree Work

Revert Tree Work for now.

This reverts commit e9b1d508be76988a7dd12459aa5e963aa9f615bd.
Revert "More tree node work and group work"

This reverts commit 4211bdf6d33303063236ae376e8d2fc575c1298b.
Revert "including tree node classes"

This reverts commit 7be22365df468fe7ec192ed6192cb0fbb3fbc730.
Merge pull request #1412 from mkly/revert_tree_work_commits

Revert tree work commits