Add icons for task navigation
Reload detailed view after validation/invalidation in the treeview
fix invalid relative task error for non relative editions
fix core dump when clicking on parent field for a top level task in detailed view
fix index bug after task modification (tree view)
Avoid edition in subtask table view
changing setCheckable to setDisable to allow dynamic modifications
add selectTask to tree controller to ensure the right task is clicked
add click validation on validIcon (treeView)