* Added the beginning of QTreeWidget and QTreeWidgetItem
* Fixed garbage collection
* Fixed garbage collection
* Rewrote the constructor for QTreeWidgetItem
* Code cleanup
* Fixed up the QTreeWidgetItem constructor to accept only a string list of columns. Code cleanup
* Add setHeaderHidden to QTreeWidget
* Started adding signals to QTreeWidget
* Started adding signals to QTreeWidget
* Started adding signals to QTreeWidget
* Added TreeWidget back to main.cpp
* Added more functions to QTreeWidgetItem and QPlainTextEdit
* linting and cleanup
* parenting fix
* Fixes garbage collection for treewidget items
