Store task UI geometry in project file

Updates various parts of the task subsystem in order to save and restore the UI node positions when projects are written and read in.

smtk/extension/qt/task/TaskEditorState.cxx

+//=========================================================================
+//  Copyright (c) Kitware, Inc.
+//  All rights reserved.
+//  See LICENSE.txt for details.
+//
+//  This software is distributed WITHOUT ANY WARRANTY; without even
+//  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+//  PURPOSE.  See the above copyright notice for more information.
+//=========================================================================
+#include "smtk/extension/qt/task/TaskEditorState.h"
+
+#include "smtk/extension/qt/task/qtTaskEditor.h"
+#include "smtk/task/Task.h"
+
+#include "nlohmann/json.hpp"
+
+namespace smtk
+{
+namespace extension
+{
+
+TaskEditorState::TaskEditorState(qtTaskEditor* taskEditor)
+: UIStateGenerator()
+, m_editor(taskEditor)
+{
+
+}
+
+nlohmann::json TaskEditorState::globalState() const
+{
+  return nlohmann::json();
+}
+
+nlohmann::json TaskEditorState::taskState(std::shared_ptr<smtk::task::Task> task) const
+{
+  return m_editor->uiStateForTask(task.get());
+}
+
+} // namespace extension
+} // namespace smtk