BuildingEd: Try again to remember/restore the current tool when switching documents/modes.
BuildingEd: Switch from WelcomeMode when opening a document that is already open.
BuildingEd: Added "hand" cursor feedback to SelectMoveRoomsTool/SelectMoveObjectTool.
BuildingEd: Added BuildingRegionItem::shape().

This was needed when calling setCursor() on the item.
BuildingEd: Changed tooltip on the "Rooms" button.

Verb FTW.
WorldEd Dock remembers the expanded levels when switching documents.
BuildingEd: SelectMoveObjectTool doesn't initiate drag when Ctrl/Shift-clicking.
BuildingEd: SelectMoveRoomsTool feedback moves user-drawn tiles.

When dragging the selected area, only rooms and objects were shown to be
moving, not user-drawn tiles.
BuildingEd: Fixed RoomSelectionItem bounding rect not being updated when level changed.
Implemented exporting to Rules.txt and Blends.txt from BmpToolDialog.
Added icon to Warnings tab in BmpToolDialog.
Fixed BmpBlender crash when BmpRules change.
BuildingEd: SelectMoveObjectTool cancels moving if the tool is deactivated.
BuildingEd: Fixed display corruption after resizing a building.

The layer-group bounds weren't being updated.
BuildingEd: Fixed multiple .autosave files per document.

A new filename was being picked every time autoSaveTimeout() was called.
WorldEd-placed Lots in adjacent maps are now displayed.

Also fixed the issue where 0_Floor* tiles under Lots in adjacent maps were
not displayed.
BuildingEd: Fixed BuildingRegionItem::buildingResized() default-parameter bug.
BuildingEd: Fixed uninitialized BaseTool::mHandCursor.
BuildingEd: Fixed crash due to not calling setCursorObject(0) after resizing a Wall object.

When the Wall's length didn't change, setCursorObject(0) wasn't called,
leaving a ResizeObjectModifier hanging around which crashed in ~ShadowBuilding()
after later resizing the building.
BuildingEd: Fixed assertion failures when selecting empty furniture in Tile Edit Mode.