Minor update for rendering fixes and new functionality.
- Made it possible to move base nodes with the base node management tool
- Added support for
DrawFlat=yesfor overlay types, meaning Tiberium, Ore and similar overlay will never overlap units anymore - Fixed overlay shadows using the wrong frame
- Fixed depth rendering of large overlays that overlap multiple cells
- (DTA) Fixed depth rendering of large terrain objects such as impassable bush and tree groups